Vincent
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Technical
Information
(each
can be enlarged)
Andy
Hopkin's Die Cast Rapide Engine
Comet Timing Gear Group. Revised 10/7/07
incorporating your comments.
(Gwilym Davies)
Higher
resolution
(revised)
copy for your parts manual.
Camshafts: I have been
told that Megacycle bought the Emmericj/Andrews cam designs. I
have those in my bike and I was told to split the overlap at TDC at
.050" lift, which is what Max, Tom, and others have basically been
saying. This means if intake opening is at 0 deg and exhaust closing is at X deg,
make the intake opening at 0 + X/2 deg. Then you can retard that
for more peak power or advance it for more low down torque. That
is over-simplified, but you bike will run fine at 0 +
x/2 deg. Bruce Metcalf
7/28/10
Shifted
Flywheels: If your feed quill shows rubbing /
wear on both ends - but on opposite sides is indication that
flywheels have shifted. For more dramatic evidence
of shifting obtain a length of quality 1/4 inch dia.
steel drill rod a foot long or better and dead straight.
Slide this up into the right side quill passage untill it bottoms
out. Give it a light tap to seat it. With someone rotating
the motor via the kicker you kneel and observe the end of that rod end
on. If it spins with a decided oval pattern to the movement
that's a pretty good indication that the flywheels have shifted. The
nearer to no wobble the better. Sid Biberman 7/28/10
Valve Timing:
All you need is one dial indicator to time the cams. Remove the
half time pinion gear from the crankshaft. With a degree wheel,
place the rear cylinder 37o before TDC. Remove all of the
pushrods except the rear intake. Place your dial indicator on the
intake valve head at the top. With your fingers, grab the idler
gear and turn until the intake is .050 open. Lock the idler and
cam teeth with a screwdriver in that position. Now you can find
the keyway slots that best time the cam in that position, by sliding
the halftime pinion gear on the crank. When this position is
found, the key should tap in or slide in rather freely. Now
rotate the crankshaft, using the attached degree wheel for reference,
410o. This will put the front cylinder 37o before TDC.
Place the dial indicator on the front cylinder intake valve stem
head. Mark the degree wheel and the pointer so as not to loose
the 37o position. Back up the engine 50o. Remove pushrod
from rear intake valve, and install intake valve pushrod on front
cylinder. Adjust properly. Rotate engine in direction of
rotation to the previously marked timing position. You should
have a reading with the front cylinder at 37o before TDC of .050 on the
dial indicator. If you don't have the .050, the front gear will
have to be pushed off of the front cam, and relocated, until you
achieve the .050. Max Lambky 7/9/11
Porting a standard head
to it's maximum requires 90o plate flange bolted to the head. The
plate flange should be 3/8" thick, and it's manifold mounting flange
studs
should be 2 1/4" from center to center.
To accomplish the mod, remove the two studs in
the cylinder head. The threads are one quarter twenty. Take
two quarter twenty Allen head screws, one inch long, and take the
outside
diameter of the Allen portion down .010. Manufacture a flange
from
aluminum, using the dimensions above. Manufacture the flange with
counter sunk mounting holes, so that the flange can be bolted to the
cylinder
head with a thin paper gasket. You can now take the port to it's
maximum size, and achieve much better flow characteristics by raising
the
port to it's maximum. You now have a wider horizontal bolt
pattern
flange, compared to the perpendicular narrower bolt pattern
flange.
Make yourself an aluminum manifold, keeping the bend as high as
possible.
The manifold should be a spigot mount, opened up, and blended to a 36mm
size. A 36mm Mikuni is my choice for carburetion. Max
Lambky 3/12/10
Valve Timing:
Timing marks may not be correct as the wheels may have been pressed off
the cams at some time, checking timing by lift is better. Equal
lift
on both inlet and exhaust at around four degrees before top dead centre
seems to be the ideal to aim for. There is no need to remove the
timing cover, just put a degree disc on as normal. I checked mine
for the overlap position and with Mk1 cams the the rear came out with
equal
lift at 7° and the front 5°. It might be possible in this
instance to play around with the timing pinion keyway to get one
cylinder
or the other closer to 4° but as it runs fine and there is no spray
from the carbs it is OK for me. You may be able to remove the valve
caps
and do a rough check by eye without dial gauges to find the "rocking"
position
of the tappets. Eddie 5/11/10
Valve Timing:
A
foursome
of dial gauges will compare lift on the front & rear
respective
cam followers by reading off the top of the pushrods while still in the
engine..50 degrees apart of course..The amount of lift should be close
at any given amount prior to ( intake ) or after ( exhaust ) TDC..gas
tank
off - mounted by magnet to the oil tank.. Bob Collings
5/11/10
Valve timing: The
valves should have equal lift at between 6 and 4 degrees BTDC.
This
works for every cam (Vincent or otherwise) I've ever timed. If inlet
and
exhaust valve closing and
opening overlap, they have to overlap somewhere,
and on every motor for which I've plotted a valve lift diagram,
"somewhere"
turns out to be about four degrees BTDC.
Tom
2/22/10
Cam Slots:
In the Richardson book, there is a drawing of the timing chest.
With
the rear cylinder at TDC, the slot on the rear cam is parallel with the
rear cylinder bore and the slot on the front cam points straight
down.
Bruce Metcalf 5/11/10
Timing Chest:
Unless the spindles are way out from being equal in height, I
would
suggest the last thing you should be doing is moving them. The
interference
in the crankcase is critical and once in place should not be messed
with
unnecessarilly. The positioning of the various types of washers and
shims
is necessary, but the number used to gain the correct result is not.
Spindles
can easily be built to the same length with the odd correctly placed
washer.
Then it is essential to get the endfloat right. It is hardly likely
that
the same size washers and shims will achieve the desired result after
over
50 years of use and replacement. Shims can be obtained in various
thicknesses
and provided you replace them in the positions originally used the
number
doesn't matter. It is only a matter of common sense to end up with a
plate
that is not distorted and the correct endfloat
on the various components. It will take some time and a few trial fits,
but the end result is well worth the trouble. Derek
Peters
1/28/10
Timing Chest:
What was not immediately obvious to me was that there are two outboard
washers on each spindle, the outermost is clamped between the plate and
the spindle, and takes the thrust. The other is the shim and runs
loose.
I reckon that 5 to 10 thou end float is OK (partly instinct, partly
because
Trevor told me so), but what is important is that the stick-out of the
spindles above the crankcase is the same otherwise the plate distorts.
They should be 0.419 to 0.424 proud. I made a slide hammer to adjust
it,
but it took a while. It was actually a very satisfying job, assembling
the timing gear piece by piece insuring that it hadn't tightened up
after
every stage. So, taking your point, I'd studdy the literature (ideally
KTB, the Instruction Sheets, and Richardson, then I'd check very
carefully
that all the shims are in place when you lift the plate (checking the
back
of the plate to make sure none are clinging there), then that all the
spindles
are the same height, then proceed. Tom Gaynor 1/28/10
I set up
big ends with .001" clearance plus or
minus a couple tenths. Dan's math is correct as usual regarding
rock.
(1/64" is good for a standard crowded roller ass. An Alfa 1/32" is
correct.
Each gives you .001 clearance. ) Rather than rely on a rocking
figure
I prefer to hone the big end eye to zero clearance hand fit then
measuring
with a bore gauge hone the required clearance. The
INA
bearings are a wonderful innovation. Amazing the load and rpm they can
handle. Steve Hamel 1/7/10
Primary case oil
level:
A simple, but time-saving mod is to remove the primary chaincase level
screw and replace it with one that projects 1/2" into the case.
Then,
if as on my bike, an erratic primary chain level merits regular
checking,
it is easy to see if the oil level is over or under the projecting
screw
by looking through the inspection cap directly above. Tom
12/14/09
Oiling procedure prior to
initial
starting : If the oil
isn't
already poured into the top member oil tank. Proceed
thusly.
About 2 & 1/2 qts will be enough if you follow these other
directions.
Then after running it a while, {even a
brief
ride twice around the block} do then. Fill to the normal
level,
ie about 3/4 inch below the filler tube. Check for leaks
afterwards
at Every banjo bolt, etc. Some loss by oozing is
common,
snug up as needed, but very carefully. Any faulty seal needs
being
replaced.
There are 4 things to do, important
if rapid wear is to be avoided .
#1 Back off about 2 turns the lower
banjo bolt at the bottom end of the large feed pipe, a pan
beneath
it. Wait till oil issues forth freely - not the early
bubbles but a clear oil flow. When you see clear oil
tighten the banjo bolt carefully { this to let the air column escape
ensuring
that oil is present at the pump entry port}. Tighten carefully so
as not to fracture. Clean off the fittings.
#2 At the forwards end of
the timing cover facing you is another banjo bolt - a longer
one.
Both hex heads are the size of a spark plug hex - 13 /16ths. When
unscrewed slide this one out. Using a
hand
held oil pump can - enter its spout into the hole about 3 or 4
inches,
this will project into the oil filter chamber - right into the center
of
the filter element. Pump this empty chamber full or nearly
so to lessen the time needed to circulate the oil when
started.
Pull out the pump and replace the banjo bolt. Carefully
tighten.
Wipe away any spilled oil.
#3 In the center of the lower
side of the big end feed quill is a small screw, remove and
pump in several strokes of oil to flood the rod big ends. Replace
the screw.
# 4 Remove the center 2 rocker
caps.
If they feel to jam Stop. Turn back inward - rotate the motor a
bit
to lower the rocker arm and try again. Now, refill
the
squirt can and pump its contents down both pushrod upper openings - 6
full
shots in each one. Replace the caps. This will flood the
cams
and followers so they won't rotate dry, then the oil will run
down
into the sump where it will be picked up by the pump to be returned to
the tank, oiling the rockers as it goes through the return pipe.
If all this is done correctly you should see oil returning
in the filler neck very soon after restarting. I'd
guess
within a minute.
#5 Check the gearbox oil level - should
show on the bottom of the stick. If not add a bit more til
it does. This holds a full quart from drained.
#6 Check the primary case level.
Oil should be up to the level plug opening and just ooze out a little
bit.
Not drip heavily. If so let it drip till it near
stops.
Replace the short bolt and just snug up, careful not to damage
the
threads. This is a steel bolt in soft alloy and
can strip. Sid 12/14/09
Checking the Valve
Timing:
I don't bother with opening and closing points, it's far too
inaccurate.
I set my engines up with both valves equally open at between 4 to 6
degrees
before TDC on the exhaust stroke, coming up to the inlet downstroke,
and
it works like a dream. You know if you are on the compression
stroke
by mistake, because at 4 degrees before TDC both valves will be
closed.
This method of valve timing is also much more accurate if the cams have
any wear. Roy Cross 11/6/09
Excessive Oil
Consumption:
Fairly
common this condition causes high oil consumption and lowered
performance,
oil fouled plugs. Sited on the bottom of
the
cases - on the right side beneath the pump chamber is a small threaded
plug with a straight slot. This short grub screw simply seals off
a drilled passage eading to the pump.
If
loose or poorly sealed air will seep in past the threads- weakening the
vacuum {suction }that lifts the oil out of the sump and delivers
it to the scavange side of the pump where it can be
returned
to the oil tank. And so the level rides higher than
normal,
wetting the flywheels where it is flung too
heavily
up the bores. If in doubt, remove this plug and
clean all threads involved, and then reseal effectively using
Permatex
or other good sealant. Allow to harden
.
Sid 10-24-09
Yes, the plug should be sealed so as to make Air Tight - and Oil
tight
! It is a cross drilling used in machining to connect
drillings
for oil pump, then sealed with the plug.. common practice. Mike
Has anybody fitted a magnetic
plug to thier oil system? How about a magnetic screw
in
the end of the oil quill? How about a magnetic plug in the
underside of banjo bolt, or even drilling and taping a thread into the
top of the banjo bolt and threading in a magnetic drain plug.
That
would catch metalic particles just before
they enter the oil pump. How about inserting a union on the
return
line to the tank and getting a plug into the wall of the flow
stream?
Richard Friedman 10/21/09
I put a magnetic sump-plug in my
Manx. When it came back from my Manx engine-building guru, the plug had
gone. I asked him if he'd lost it. "No, I took it out. Magnetic plugs
collect
metallic particles, and Manx motors Always shed magnetic particles. So
why stress out by collecting them, and agonising over them? They'll be
there anyway." So I left it out. The bike still runs, lambs still
gambol
in the meadows, the sun still shines, and there's one inevitable thing
less to worry about.
Think of it like worrying about death. What's the point? You Are going
to die. Vincent (and Manx Norton) motors Are going to shed magnetic
particles.
Why dwell on it? To paraphrase, someone recently quoted PEI as saying
"if
it isn't making distressing noises, forget mileage, ride it". With
earplugs,
my constant recourse, Vincent riding is a virtually stress-free
occupation.
And when I pull the non-magnetic drain-plug for an oil-change, it
remains
stress free. Tom 10/22/09
Bend a bit of SS lock wire into a kinda cage containing a small
strong magnet and form a loop
that locates it beneath the returning oil squirt, so that
the
oil flows over it. Hang the loop over the chain oiler adj.
screw. Sid 10/17/09.
Easy to check breather timing
without disassembly. Blow into the breather pipe while turning
the
engine over, breather should close just after (30 deg) BDC of rear
pot.
Paul Zell 9/2009
A Manx pump is reckoned to deliver 42 gph at 7200,
which
is 0.77 pints per 1000 rpm. The Vincent oil
pump
delivers about 0.15 pints/1000 rpm, a modern Ducati delivers about 6
pints/1000
rpm. Sunbeam 8/19/09
The original Picador two-start oil pump
mod consisted of just a "magic ring", a higher pitch drive worm, which
turns the stock pump faster. Later and current two start pumps come as
matched sets that require a matching worm and pump, and are not
interchangeable
with the early one. Steve Lindbloom 8/19/09
2 start oil pump: I
don't violently disagree with david, but my oiled plugs problems were
cured
by fitting new pistons in new, cylindrical muffs, and replacing
my (worn) valves and guides with new valves and
sealed guides. Granted, at 48,000 miles, this was due, if not
overdue.
Make sure you buy a two-start worm. Perhaps it was the way I read
the
literature, but it wasn't initially clear to me that that is
essential.
I'm not sure about the "excess oil" argument. A two-start pump
scavenges at double speed too. On balance, I'd
say one has nothing to lose by going two-start. It'll give you
about
1/2 litre per 1000 revs.
My Ducati Monster delivers 35 per 1000
revs.
Personally I reckon much "oiled plug" trouble is caused by
running
plugs that are far too cold. Before the overhaul I reduced my oily plug
problem by 50% by changing my NGK 6's to 5's. 6's didn't get hot enough
to burn the oil off. Tom 8/14/09
Cylinder Liners:
L.A. Sleeves offer well proven -well made liners in oversize
dimensions
used with full success for many years. Coventry Spares generally
carry liners in + 40 and + 60 at reaonable
prices of fine quality. After removal and deep cleaning, a
pair of finned cylinders are closely examined and measured /
compared
, the purose being to Blue-print them to identical thickness top to
bottom
as well as being bored perfectly central and perpendicular to parallel
top and
bottom surfaces. Their inner bores are taken
out enough to fully clean-up and provide a smooth dead straight and
round
surface. Unwise to bore any larger than necessary as it
loses
cylinder strength /rigidty. The new liner is mounted on
exanding
mandrels and it's outside diameter is reduced dead true to its center
and
fully larger by .004" than the i.d.of that muff selected to mate
with it. At the exact distance from it's top where this liner
shall
emerge from the bottom of that muff -this sleeve is taken down to suit
one or the other main case register mouth bores - to a fine finish and
a snug slide-in fit into the bolted together cases, and marked to
identify
this mating for correct assembly. The remaining liner and
muff
are likewise prepared and mated. The cool liners are fully
entered
into the heated alloy muffs and held hard-in until cooled off.
The
top recess and head spigot already having been reformed to original
dimensions.
Later, after final double grit lapping, we like to see an air gap
of
.003" between the two broad faces, the differance in grain size.
This will close up and come solid upon application of the correct
torque
loading figure, i.e. 30 to 32 ft.lbs. maximum. No
more
is needed and actually harmful. Before final bore and hone
procedure,
the thrust face oil delivery holes are sited
carefully,
these to break through below the oil-ring grooves - at BDC - not into
them.
Finally we prefer to fit a lower liner mouth girdle clamp to prevent
any
bell -mouthing while boring and honing. Sid
7/15/09
Broken nuts on locking
rocker feed bolts is not an unheard of
problem. People seem to not take into account that the load exerted by
188, the banjo bolt, is transferred down through ET100 mod. to the
rocker
feed bolt nut. If one of the banjos is leaking and 188 seems loose,
suspect
that the RFB nut may be broken and pulling up. Phelps
6/30/09
Always run a small drill bit with your Fingers into
the
1/4 x 20 threaded primary and timing
case
holes in the crankcase before
inserting
new cover screws. The bottom fills up with RTV and all sorts of grit
and
debris ( from previous owners..) and the screws can strip the case
threads
by hydraulic lock. Jim 6/22/09
Locking Rocker Feed
Bolts
:
Open up the rocker bush top hole from 5/16 "
to 3 / 8 " for top hat nut to fit inside.
De- burr and dress to fit properly.
Ensure oil feed holes are not blocked .
Top of rocker will need grinding to clear
the top hat nut as it will bind on full movement.
Use a slightly undersize 1/2 " rod or old bolt
as mandrel for checking instead of keep inserting and
removing
rocker pin.
Check to see rocker pin is not too long as will
bind on tunnel when fitting.
Remove any metal chips or dirt etc. from all
parts. Grease and install . Mike
White
6/20/09
Head Nut Torque: PEI
gave me this figure. 30 to 32 ft lbs.
This
leaves a natural " give " or elasticity necessary in
the long studs to allow column growth when fully
hot.
Apply in stages criss cross, leave sitting overnite, re
check
the following day. Sid 6/17/09
Welding
rod 4043 will work perfectly for the Vincent
crankcases. The main consideration is
cleanliness. Cases should be pre-heated and a stainless steel brush
used
for cleaning. If a grinding wheel is used ( to Vee a section for
example)
make sure you do not use a wheel that will ultimately contaminate the
aluminum.
Thus, if you can use only a file to "vee" your part, do so. After
heating
the part once to clean it, and clean is the most important word here
(if
you are welding a part that was subjected to oil, the devilsh stuff
will
work its way to the surface easily) the part should be pre-heated to
200-300
degrees. You can check it with a heat stick available at any welding
supply
house. Of course I am referring to welding the piece with a
heliarc
(TIG welder). Carl Hungness 5/23/09
A D breather cap
will take a double ended BSP fitting as used in a fuel petcock. It
screws
right in. Such a fitting, with BSP at both ends, will take a one
inch length of 1/2 inch ID rubber fuel line, the
distal
end of which will take a pcv valve with a 90 degree bend,
easily
purchased at any aftermarket auto parts store. I used a hose clamp
("jubilee")
to secure the hose segment to the distal end of the double ended
fitting.The
above setup, when placed on the rear cylinder inlet rocker area, seems
to me to allow maximal flow as the rear cylinder set up is a straight
shot
to the timing chest with a big orifice as compared to the 2nd
cylinder
exhaust. Plus the pcv valve can be postioned perfectly horizontal
in thisposition with minimal distance between the cap and
pcv.valve.
You then run a short length of fuel line from the vertical end of the
pcv
and it goes between the back of the crankcase and the RFM, or you
could run it to your chain if you preferred. All of this was done after
blocking of the original breather orifice with the brass plug. Most of
this I stole from others, but the series D cap the 1st cylinder inlet
valve
cap position, the BSP double ended fitting, the short run between
the valve, the ability to position the valve horizontally with a
subsequent
vertical run seems a happy combination. I've got a lot of other
pcv
valves and hoses and other positions I tried! Charles
Cannon
5/15/09
The answer to getting
an oil-tight bike lies in the
accumulated
knowledge of hundreds of Vincent owners. The problem is getting all of
that knowledge into one bike!
Rocker oil feed banjos:
1. If they have been chromed-many plating
companies
hang such parts in the plating tank on a twist of wire. This leaves a
tiny
groove in the plate across the mating surface, through which oil will
seep.
I always rub my banjos on a flat piece of emery paper to get a totally
flat surface.
2. Most banjos have become slightly dished over
the years, from the 1/4" BSF bolt head, so I invert the rubbing process
to return the upper face to a flat surface.
3. It is a good idea to change the normal 1/4"
BSF bolt to an AMAL carb petrol
feed bolt, which has a 1/4" thread, but has the
head of a 5/16", thus spreading the pressure over a wider area of the
copper
washer and avoiding the dishing in the future. These bolts are
available
in stainless.
4. I always drill and wirelock the rocker oil
feed bolts, as they tend to slacken slightly. (See 6)
5. Ensure that the bends in your oil feed pipes
align the joints properly into the union, so that the conical ends fit
square into the union. (I have cheated on two of my engines by using
flexible
Aeroquip hose, thus the union can align itself).
6.The ET189 fibre washers tend to flatten in
use, thus spreading, getting thinner, spreading some more, and
eventually
splitting. Either use a suitable Dowty washer, or Neal Videans new
washers,
or as I have done, turn some aluminum rings to fit exactly round the
ET189s,
which stops them spreading and so they don't get thinner, which loosens
the bolt.
If you do all the above, your rocker oil feeds
will be oiltight. Dick Sherwin 4/24/09
The traditional way to measure
gears is the over-the-pins method.
If you just want to grade them from small to
large,
find two rollers (bearing rollers) that fit approximately 1/2 way into
the tooth space. Place them between opposite sets of teeth (for
even
teeth) or staggered by one tooth opposite (for odd numbers of teeth)
and
measure acccross the pins. You will probably find this will vary
if you work your way around the gear taking successive
measurements.
This could be due to wear or pitch diameter run out. Another
useful
way to gage your gear is to rubber band a set of rollers around the
entire
gear and spin the gear on centers with a the rollers passing a test
indicator.
This will give you a sense of the pitch diameter run out with respect
to
the axis of rotation.
Sophisticated gear manufactures make a test
gear
to exact dimensions and run the manufactured gear spring loaded against
the test gear. Then then measure the displacement of the
manufactured
gears axis as it rotates. This provides a quick cumulative
measure
of the inaccuracies that result from gear manufacture.
No gear is perfect. You need to set up
your
gears so that there is zero interferance in the worst case condition
and
live with the noise as your imperfect gear rotates into positions where
the mesh is less than ideal.
Incidentally, when a gear tooth is
transmitting
power it deflects a tiny bit, so that the set of gear teeth about to
come
into contact are no longer synchronized and they collide a tiny bit
when
they first touch. You can see this on some gears as evidenced by
a contact line across the gear at about 2/3 of the gear tooth
height.
Fancy gears have the profile slightly backed off at this location for
improved
durability. Another solution is to use an aluminum gear whose
sacrificial
soft surface will abrade away to provide optimum
performance.
Richard Friedman 4/15/09
Routing Oil Lines:
When I did the Prince, the feed tube was a little battered and the
Spares
co. was out of stock. I cut off the battered length and increased the
length
of the herringbone flex hose. I have since obtained a new feed pipe but
haven't yet fitted it. One reason is when I fitted the the longer hose
I borrowed a ferrule clamp which nips the hose/pipe very tightly and I
am loathe to remove it. Two advantages of leaving alone, first it is
hidden
behind the side panel and two, by slackening the oil feed union I can
swivel
the pipe out of the way when removing the kickstart cover, with only a
slight drip of oil. Paul Craven 4/17/09
Routing Oil Feed and Return
Lines:
I concluded that what you want is impossible. I grew tired of
dismantling
the entire bicycle to get the kick-start cover off. Since I don't care
much about originality (although I do care about aesthetics, see recent
posts about Italian bikes), I inserted a piece of herringbone (i.e.
authentic...)
tubing, in the feed line and took the oil feed BEHIND the rear engine
plate,
tie-wrapped on to the plate to stop it drifting into the rear chain.
Now
I can wiggle the kickstart cover off past the return line (the one to
the
rockers) without disturbing either feed or return. (Feed's the one that
creates a 6 foot pool of oil under the bike when disconnected at either
end.) Although prejudiced in my own favour, naturally, it doesn't
immediately strike the eye as Wrong. Tom 4/14/09
Oil Lines: Dick
Sherwin cuts his pipes off near the banjo's and fits braided aircraft
type
flexible armoured tube in the gaps. All very neat. Roy
Cross
4/14/09
Bending Oil Lines:Fill
em with cerrobend and bend em by hand then melt out with boiling water.
Tom Kingman
Bending Oil Lines:
My still-making friends use salt - you have to crimp the ends to hold
it
in, but it's cheap, and easy to dissolve afterwards (I've known plenty
of people who have tried sand, and never could get it out again).
Bending Oil Lines:
You can use this to bend your tubing. Heat tubing in hot water 200F
with
the bottom end plugged. Heat Bismuth to 200F in a container sitting in
the water.
Pore the metal into the hot tubing, still sitting
in the hot water. using a small funnel made from what ever is handy.
Now bend the tubing as you wish. Tubing
will not collapse as it is now a solid.
http://www.mcmaster.com/#metal-alloy-casting-compounds/=1ghxoz
Ken Smith 4/15/09
Head Joint: With
correct machining to the top and bottom surfaces and good
lapping
technique there will be an air gap between the broad faces with
the
head placed firmly home on the spigot, the liner top edge
sitting
properly within its recess. All surfaces clean
of
compound and debree of course. A feeler gauge
of
3 or 4 thou. should enter that gap without forcing the head to
rise.
If not it will not seal, the actual sealing occuring Not at
the broad face --- but at the narrow inner surface, iron
against
alloy. The described gap will vanish when
the
assembly is torqued down, and if correct in
every
way 32 max ft lbs should be sufficient,
30
being usually sufficient for a street motor .
More
won't solve the problem --- but if severly
overloaded
shall certainly introduce more troubles
with
the motor at full heat . There will be no easy answer
until this important detail is dealt with -
through
correct preparation in the machine shop of the spigot /
liner
dimensions. And be sure the liner is fully home in
the
muff or it will drop further spoiling the work .
Sid
12/6/08
Head Joint: If
the head has been on for years creep will have taken place and
the
gap will have disappeared. It is essential to check for the gap
when
replacing the head. I found it easier to stick some coarse
wet and dry to a board and rub the head on it to remove 2 thou.
Then
just grind the liner joint with fine paste. Ernie Lowinger
12/5/08
Timing Gear
Backlash:
The problem is Not in the idler gear but in both camshaft gears,
common with high mileage cams. There is a cyclic wear pattern
caused
by the nature of their work loading, alternately forcing
the
springs to compress {thus the wear occuring on one side of the teeth
flanks}
followed by those same springs driving the idler gear - with a thrust
reversal
- { they rack back and forth as a result } the wear now on the
opposite
teeth flanks. But seen on only those teeth doing the
heavy work - not all. The condition is permanent, only
corrected
by replacing the two pinions { the shafts can be reused if
unworn. Generally the only downside is a noise generated
during
running , and if you set set the idler position to that
compromise
location where you can just slide out the big gear with your fingertips
- then that is the best you can do, this with the
Least
or nil lash discernable. There will still be
those
periods where looseness can be felt And heard {as the
cam gears rack back and forth doing their work against the spring
pressure}
but its not a danger, only unpleasant and
noisy...
Or replace the gears. Be sure these are
correctly
located on the shafts - critical - and a spot of weld will keep
thm
there. Sid 12/5/08
Mufflers - Cams: Straight
through Toga muffler Toga works well with Mk 2 cams and the original
spiral
baffled muffler will work okay with Robinson 105 cams due to
reduced
overlap. Carleton 8/18/08
Vincent liners are
very often far from round for many reasons besides being perhaps
poorly machined. Fit in the muff which might itself
be
far from true, also often loose and thus offering uneven
support
to the liner within as well as causing liner overheating due to
poor
thermal path to the fins. Also a common fault
is
overtorqued head nuts causing severe stress to the cylinder structure
when
hot, and the muff might not have parallel top and bottom faces
thus
causing a twist. All will cause the rings to work
harder
trying to follow the liners uneven surface. With a similar
history it's likely that similar problems will be found to exist
in both cylinders of a twin. A careless/read cheap
rebuild
will often have the barrels rebored without knowing that the critical
liner
to muff fit is suitable in all the above
details,
and can lead to many headaches with a Vincent motor not limited to the
complaint mentioned but also to severe ring blowby, heavy oil
consumption,
fouled plugs and poor performance. None of this necessary or
the
fault of the design. Dont curse your Vincent
----
but blame the machinest. Or a
tightwad
owner choosing the cheapest way to go.
Sid
12/23/07
Timing Chest:
If you were to fit all the listed washers in their correct location and
then adjust all the spindles to give the correct end float then
you
will more than likely end up with the steady plate being warped all
over
the place. The correct procedure is to set all the spindle
shoulders
to the specified distance above the timing chest face. Then shim the
various
components to give minimal end float. Whilst doing this align the
followers
so they fall centrally on the cam lobes. If you end up have to use a
couple
of extra shims then so be it. An alternative is to use thinner
shims
or spacer washers. The front cam spindle coming out at
temperature
can be resolved by refitting with loctite whilst still hot, be quick
though.
Phelps. 10/26/07
The explanation for there being no (or no need) for thrust
washers behind components is in KTB. What thrust loads
there
are are towards the outside. MO13 is wrong (and it is). KTB shows
corrections.
anon
Timing Chest: The
shoulders of the spindles should be
0.419"
to 0.423" proud of the cover joint face. (KTB Page 154) and they all
need
to be tight and in order to move them the crankcase should be heated
locally.
The spindles should ideally be fitted with the oil holes on the
underside
since that's where the clearance is.
The idler gear should be meshed with the camwheels with no backlash.
The half time pinion should have no more than .002" backlash. (Works
instruction
sheet No.6). Whilst you've got the opportunity I think that it's
worth fitting the later type valve lifter as both valves can be lifted
together. (Details in KTB Page 163)
A small mod. that I find is worth doing is to counterbore the pushrod
tube nuts about 1/32" oversize to allow for the mis-alignment which
occurs
with varying height of the cylinder muffs.. Roy Cross
10/25/07
ESA Springs: In
my experiance the main cause of breakage is
found
in the varing depths of the drilled holes - and
or these are packed up at their bottoms with
debree
from previously broken remnants .
This
leads to coil binding with early breakage as a result
. Check and clean out all holes with a drill
bit
making sure that all are of equal depth ,
and
if needed deepen to acheve this .
Before
assembly grease all the springs with disc brake
type bearing grease { HMP }
,
and coil direction will not prove a factor
.
Of course if the outer nut wanders
loose
many bad things will happen so be sure this
goes
fully home and is secure using Loc
Nut
{ threads to be really clean first
} or other means / or both .
DO NOT brutally force this nut with
excessive torque beyond the assembly going fully
home
as one can shift the mainshaft Mills pin
. Select the best lobe nesting
position
for least movement before the outer component
begins
to lift . This makes for more supple
functioning
of the ESA and longer component life
.
Sid .
MK 2 Cams: PEI
autobiography, page 374. "I decided to retain the exhaust opening and
the
inlet closing timings of the Mark 1 cams but alter the exhaust opening
and inlet closing angles to widen the overlap to 105 degrees and
subsequently
increase the valve opening during the inlet and exhaust strokes. The
full
lifts were also increased from .312ins to .343ins". Roy
Cross
9/4/07
There seems to be an assumption by some that the cam
lift is the same as valve lift, which
I believe is not the case. Although the standard rockers are not
ratioed
(is there such a word?), that is they are 1:1, the physical positioning
of the various parts of the train of components gives a ratio which
increases
the valve lift above that of the cam lobe by about 1.12 .. Thus Roy's
quote
from Phil Irving of 0.343 (if taken as cam lift), when multiplied by
1.12
gives 0.384, which falls into the ballpark of the valve lifts quoted in
practice. Try measuring your cam lobe against your valve
lift
as I have just done. Not certain if this has any practical application,
though.
Dick Sherwin 9/4/07
Cam Lift and Valve Lift:
The
latter
will be greater because of the amplification via the
cam-follower
arm. The question now becomes: What is that amplification
factor?
It would need an original factory timing-case drawing to discover the
relative
centre-lines between cam-follower pivot, cam and pushrod-cup. I'm
not aware that such a drawing exists. Peter Barker 9/4/07
Cam and Valve Lift: There are two
amplifications. One is straight arm length: a 2" radius at the valve
and
1" at the cam follower gives 2:1. But each radius varies as the contact
line between cam-follower (or rocker) and cam moves, and the contact
point
at the valve changes too. I think that PEI discusses this in Tuning for
Speed. Tom Gaynor 9/4/07
One "top tuning tip" is to increase the radius of the
cam follower or rocker, which increases valve
acceleration. The ratio Is variable, lifting at the tip of
the
rocker / cam follower initially, and in the centre at full lift, a
difference
of about 1/4". There's a much smaller variation where rocker touches
valve.
Vins have flat cam followers (or more accurately cam followers of
infinite
radius....) but the both radii vary through each cycle. Tom
Gaynor
9/4/07
Ernesto's trick to reducing
oil
leaks: He removes the chain oiler fitting, T29, and
the
Chain Oiler screw in the oil tank is left Open. The stock breather
banjo/pipe
is plugged, so it will remain stock in appearance, (doesn't want to
offend
judges, ya' know:). After first screwing down hard the intake
valve
inspection cap for the #1 (rear) cylinder, a punch marks the spot on
the
shoulder of the cap that is up (12 o'clock). He then drills/taps and
screws
in what looks like a hose fitting nozzle. Next, a spare A71S
breather
pipe is bent (shortened, too, maybe?) in a convoluted way so that it
can
be fitted with an oil banjo to the hole where T29 is normally placed.
Lastly,
he connects the end of the pipe to the little nozzle with a short
length
of hose. Whether or not he drills open the oil cap like Big Sid
recommends,
I don't know. So far, I know of none of his tanks exploding, oil pumps
failing, exhaust smoking, etc., and I have seen at least one of his
machines
red-lined. Oil leaks on his machines? "Nada."
Ernesto is also an aircraft mechanic and restorer, and commented
that
he made changes to aircraft to reduce oil on the tarmac (and the
aircraft!)
and this was approved by their aviation inspectors. He figured he could
improve on the Vincent's breathing arrangement, also.
So far, looking at several of his machines, none leak from the
breather,
that I can tell. In fact, I see no leaks, anywhere, so either their
owners
have a handy rag at all times or he's doing effective stuff toward no
leaks.
The pipe bending is definitely the only item that a bloke like me would
struggle with, in doing this fix. I can see that other adaptations
might
work, regarding that. Anyway, this set-up appears to be a breather leak
stoppage, as opposed to minimization. Bev Bowen 9/4/07
Oil
loss out the dynamo drive
opening
if more than mist is most likely due to the fit of ET 164 in the
back case wall allowing oil flung off the chain onto the back
wall
to slip down behind this component and the wall - after which it
escapes to the outside in large quantities. Everyone blames the
apparent
simplicity of the system found to prevent leakage around the dyno
shaft but this is seldom the cause. Remove ET 164
and
straighten any dings in it, clean the surface and that of the wall all
aroundwhere it goes Seal nicely with RTV compound and tap
back
into plac . Also build up a mound around its rim with
RTV
to help it shed the oil flowing across it. Leave
sitting
24 hours with the Dyno cover off to harden.
Pressurized
cases are due entirely to massive ring blowby, usually caused by out of
round / buckled liners done in by poorly
fitting
muffs. Often the cause for this is overtorqued maln
headnuts
which doom the top half to all manner of ills, unable then to
expand
as designed, causing crushing / distortion of the
cylinder
assemblies, which overwhelm the rings ablities to seal against
combustion
pressures against the now out of round / no longer straight
walls.
A brief ride goes OK , but sustained speed drives up the heat and
distortion
rears its destructive head. None of this a fault of
design,
but directly due to improper assembly. With proper
preparation
of the head and cylinder joint urfaces no more than
30
to 32 ft. lbs. torque is required to maintain a leak
free joint. This leaves a natural elasticity in
the big studs that allows the alloy column to expand as
necessary
under peak engine heat and contract upon cooling.
Sid
9/4/07
Timing chest thrust washers:
While there exists very powerful endwise thrust upon followers from the
pushrods being tilted off the vertical - the camshafts get little
or none, they simply spin round happy with no more than 3 to 5 thou.
end
float. Thus there will be no marking of the rear wall
surface.
And no noise arises from this source Sid . 1/30/07
Generally, when restoring a vincent, the engine has
been
sitting for some time. During assembly I spray the cams and
followers
with molybond. Here is what I do when starting
up a "new" engine. Inject/pour oil down each pushrod tube,
this
floods the cam and follower area. Remove the ATD cover and fill the
crankcase
up to the the ATD opening. replace the cover. Remove the spark plugs
and
with the bike in gear, push it around or run it on rollers until
oil issues from the spout in the oil tank. This liberally! coats all
the
moving parts within the engine. Drain the sump and pour the oil into
the
oil tank. Put the correct amount of oil into the chaincase and
gear box. Start the engine and run it at a fast idle to warm it
up.
Phelps. 12/20/06
Chronological order of Idler
Gears
- first bronze, then the forged alloy one. The idler
boss was the two piece shown in the parts list, alloy with steel
pin.. The steel based one did not appear until the D`s arrived, the
works having found out that the alloy ones were lacking, when the
spindles
worked
loose. So all those machines betweemn the bronze idler and the steel
idler boss, had the ET173 fitted. Trevor 11/29/06
Gary Robinson "105" cams: These
cams have Mk II profiles but modified overlap, around 95 degrees
instead
of 105. They are 'timed' by setting the inlet valve at maximum
lift
105 dgrees after TDC. This gives a balanced overlap with
the
inlet opening 47 degrees BTDC and the exhaust closing 47 degrees
ATDC. Brian Hill. 8/10/06
Carillio Rods:
Mk 1,s Had plain 1" gudgeon
pin hole . No modification needed to fit to wheels.
Mk 2`s Also had plain 1" pin hole, but
needed to be modified , by either machining the rod or the head of the
mainshaft.
Mk 3`s Has the bronzed in eye, and also
need to have modifications to fit.
Trevor 3/17/06
Flywheel Alignment:
It's worth taking pains to get the crank assembly nicely aligned. In my
experience the smoothnes of the engine depends on this rather than
balance
factor. If you're mounting the assembly on centres in order to check
the
alignment you may find that you have to carefully scrape out the
centres
to bring them true with the bearing journals in order to check the
alignment..
If you can mount the assembly on the journals that doesn't apply. The
works
instruction sheets says - "There should be no difficulty in
getting
the shafts to run true within 0.002 inches total indicator reading".
Unfortunately,
fifty years later, this condition is not always easy to achieve. If you
measure the thickness of the side plates E16 you will find that they
are
very rarely exactly parallel but will give you a micrometer reading
which
varies by a few tenths of a thou' as you go around the surface.By
turning
a side plate to a different position you can significantly improve the
alignment. It's somewhat tedious but makes a world of difference to the
result. One point worthy of caution which I've never seen in print.
When
you've got the engine built up and you've just finished timing the
valves
and you're about to finally tighten up the E80 nut holding the half
time
pinion on the end of the timing side mainshaft. In order to do this
satisfactorily
you need to stop the crank from rotating. On no account should you
attempt
to do this by locking the primary drive as it's possible then to
displace
the flywheel on the crankpin. The method I use is to hold a spare half
time pinion in mesh with the half time pinion and the idler gear whilst
I tighten up the nut. Dave Hills brings a piston up on the compression
stroke and feeds a length of clothes line through the plug hole and
locks
the piston against it. Both ways work.
Roy Cross 2/27/06
Valve lift: The
rockers are 1:1 that is the distance one end goes up is the distance
the
other end goes down. I would remove the gas tank and use a magnetic
mount
on the UFM to position the dial gauge over the adjusting bolt on the
valve
being timed and measure the ups 'n downs. You don't need to actually be
on the valve itself. No fittings needed. Mike Hebb 2/4/06
Oil Pumps:
The very fastest of classic racers (92 and 95 bore OHC singles revving
to 9 or 10), use plain bearing big-ends. Revs are presumably valve
limited
(two huge valves.....) because the limit on a needle roller big-end
like
mine is 8. I have no wish to find out. Both use standard Norton
oil-pumps
(with a Cosworth made restrictor to the cambox for a plain bearing). A
Norton oil pump delivers about 6 pints a minute compared with 1 for a
Vin.
Oil drag seems not to be a concern for Manx's although the top spec
engines
cost £27,000 plus VAT and there is a lot of money ploughed into
development.
(Gearbox and everything else is extra. You're probably looking at
£35,000
+ VAT for a complete bike.) For comparison, the 900 Ducati
Monster
delivers about 5 pints per minute per 1000 rpm, so it is circulating 35
pints per minute at 7. An interesting question is whether or not Suzuki
would consider the Ducati pump high or low flow. They'd probably
dismiss
the Vin pump as non-functional but leaking. Tom
Gaynor
12/21/05
Vincent camshafts: I
am reminded of the need to ensure maximum flow through the
drilled
lobe passages and the need to run a drill bit through them rather than
simply relying on a blow through with compressed air. One
finds
nearly always a build up of debree or even material left
there
during the shaping and final grinding process. Only the
careful
introduction of a correctly sized drill bit will remove this crud
and these can often be found at your local Model Shop
. There we were pleased to find loose bits stocked in a
wide
range of sizes - indexed in thousandths of an inch. We were
very lucky to find a set of Andrews Mk.2
cams
at Coventry Spares, examination revealed that these
absolutely
unused cams were drilled with a 54 thou. diameter
hole
and even these were fouled somewhat in 3 of the holes and
indeed
one lobe had not been drilled through the inner bronze
bushing
at all. Other cams on hand in my shop showed variaions in hole
size
and all needing a run through to fully clear the
drillings.
As the lobe to follower interface is under intense pressure and
friction,
here is one location where rapid wear often occurs, and
thus
the need for attention to such tiny details is of paramont
importance.
Another is the two tiny drill ways in each rocker bushing
meant
to feed oil to the rocker pin and all moving surfaces
nearby
which encludes the followers and cams down below in the
timing
chest. All depend on this same flow for their reliability and
satisfactory
service life. S.M. Biberman (5-26-05)
Valve Lifter Assy: With
your timing cover off, it is just a matter of peeping in with a
flashlight
to see what is unshipped or deranged. The cable and
rod must pull the levers in the timing chest
together and the small ends of the levers must push up the camfollowers
to open the exhaust valves, yet when the rod is not pulled, the small
ends
of the said levers must clear the bottoms of the
camfollowers.
The mechanism is straightforward, but if not familiar with it you may
need
to refer to the Richardson book to get it 100% right. Sometimes
the
return spring could break. And the two levers have to be
synchronized
by the adjustment of the connecting link. And there must be the
right
clearance twixt small ends and camfollower bottoms when the latter are
on the base circles of the cams. As someone else mentioned here
the
small end I'm talking about has a 3 x 5 mm roller in it to do the
actual
lifting, which is peened in place, and it is not unknown for this to get
knocked out if the valve lifter is operated at
anything over idling rpm.
I might mention also that the valve lifter kit
probably best suits the Mark 1 and 3 standard cams. The Mark 2 BL
cam has a smaller base circle to get a higher lift. The Black
Lightning
with the Mark 2 cams did not usually have a valve lifter fitted, but
sometimes
it did. If the valve lifter is used with Mark 2 cams it needs
extra
care in fitting and adjusting because of the differences
mentioned.
But it always needs care in fitting any time any of the pieces and
parts
involved are replaced anyway. Heck, let's face it, Everything on
a Vincent needs care in fitting! Bill H. (5-15-05)
Valve Guide Seals:
Ron Kemp supplies a seal kit that works. You remove the guide
lock
rings, ET122 and ET122/1 and machine the guide down flush with the
collar on the valve guide. This can be done with a piloted
counterbore
cutter in a pillar drill or with a slot drill; in a milling
machine.You
then fit the replacement lock rings which Ron supplies. These
have
a counterbore in the bottom so that when they are screwed down on
the guide you have an annular groove to take the square section
seals
provided. However, the guide rings are machined undersize so that
they can be reamed in line with the guide to provide a bit more
support
for the valve. the seals can then be eased into place and the
valves
and springs re-assembled. A word of caution. Take the sharp edge
off the corner of the valve stem where the larger diameter meets
the smaller one to avoid cutting the seal when the valve is
inserted.
I fitted these seals to my three twins about five or six years
ago
and haven't fouled up a plug since. Roy Cross 5/14/05
The use of silicone sealant
should not cause anyone cause for concern. As with many things,
misuse
of the product it blamed on the product itself. To use silicone
correctly
as a gasket replacement takes a bit of care. First one should clean the
mating surfaces with careful use of a solvent like lacquer thiner or
mineral
spirits ...clean , as can be on both mating surfaces. Then spread a
THIN
smear of silicone sealant about the joint. Then use one's finger to
remove
any surplus sealant from the inside of the joint by just running the
finger
around the inside of the (let's say) cover to remove any surplus
sealant
from the inside edge. If you do this correctly, you will create a
little
space (on the inside) for the silicone to fill without making an inside
surplus "bead". This is difficult in some of the thinner joints as
those
found it the timing case cover. Just make sure that all is coated with
a thin smear..... meaning, about matchbook cover thickness. The
important
part is to assemble the cover, with sealant, just snug enough to allow
a little sealant to squeeze to the outside. Again, the cover should not
be fully tight because one does not want to force OUT the sealant. With
the cover just "snugged" up allow the silicone to cure and thus the
thickness
of this now solid material (sealant) becomes a real gasket ..... rather
than stuff forced out of place due to fully tightening while "wet". I
allow
24 hours to pass before fully tightening the cover. I believe one can
see
the general logic here, you want to have a fully cured rubber gasket to
tighten upon. Yes, good results take time........ so, what's
new?
P.S. : Isn't it nice that they make grey silicone for Rapides and
Black for that other thing. Rip Tragle ( born
again
Luddite) 7/24/04
Historical note: one-start, two-start oil
pumps. P.C. Vincent told us himself about 40 years ago
that the two-start worm was a desperation measure on Picador
development.
He had no two-start plungers so got some two-start worms made and used
them with the standard one-start plunger to double the oil delivery for
the Picador to keep the big-end bearings working for the prolonged (24
hour?) full-power official acceptance test. PCV said they knew it
wasn't correct, but it worked okay and the wear from the mis-matched
parts
was not excessive. George Brown and others used two-start worms
with
one-start plungers in their racing twins in the old days. Only in
recent times did someone make two-start plungers to match the two-start
worms.
I won't re-hash the question of whether double-speed pumps are
necessary
or desirable, but as P.E. Irving pointed out in his autobiography, all
the great national and world records set by Vincents back in the golden
age used one-start worms and plungers. Bill Hoddinott
7/24/04
Tightening the ESA nut:
Place
the
motor in fourth gear. Lock up both rear brakes hard by
tightening the wingnuts. Run a wooden broom handle through
the rear wheel - through between the spokes at rim level, with
the
rearstand down. The handle lying behind the stand legs. The
object is to have the motor rotated to bring up the up against the
stand
legs , now the resistance is shared by both brakes and
wooden
handle and that spoke nipple. No damage will be done if this
method
is
employed correctly. I use 90 psi air pressure driving my
half inch impact driver and the proper socket, this ground flat on
its face to secure full grip on the nut. Loc-nut grade Loc-tite
on the outer half of the threads, these both cleaned of oil. Make
sure the assembly is guiding the washer home on the splines, not
butting
end on. Using less than full on the power adjustor and
leaning heavily against the wrench proceed to spin it up in several
short applications while watching the components embrace and
close-up
against the springs pressure. The nut will come home and slow its
turning as the travel is closed up. As it comes to rest and is
seen
stopping its smooth motion, fighting further movement -- stop .
If
you persist and beat against those obvious signs to quit you can
turn the mainshaft in the flywheel , sheering the Mills pin in the
process.
The same process - with the handle in front of the stand legs will
serve
to loosen the nut. S.M. Biberman 2/24/04
PD 7 ESA: The bar
between the sprockets can be further improved on. A piece of 1" or 1
1/4"
by 1/4", 4 1/2" long. The length is not super critical. Across each end
weld, braze, bronze or silver solder, neatly, a piece of 1/4" rod. Make
one higher and one lower from the centre line. These bits of rod are
there
to fit neatly into the root of the tooth form therefore keeping the
load
low down on the tooth. Phelps 2/24/04
Diecast case external
features:
a
different font for the Vincent name on the drive side, much slimmer,
clearer
to read and more precise than the same on the sandcast case; no excess
metal around various bolt bosses; a smoother finish to the casting
without
the characteristic sand-grain of a sandcasting. Maybe some lines
on the casting from the parting joints of the die, can't remember this
one for sure. Bill 8/13/03
Diecast case external
features: Under the dynamo, there is
a
cast in depression. Bruce Metcalf 8/13/03
Die Cast Cases: Phil
Irving told me himself that he drew up the improvements that were used
in the diecast case before he left the firm and went back to Australia
in '49, but for some reason they weren't implemented in production
until
years later.
For those who have never seen a diecast case,
let me mention the improvements more specifically:
Better dimensional control, less weight by
avoidance
of surplus material.
Camplate spindle boss greatly strengthened,
made
a full-width boss in the gearbox ceiling.
Camplate actuating bevel boss also made more
massive
and continuous, although unlike the spindle boss, I never heard of any
breakage on this.
More metal around the main bearings to hold
onto
them more reliably (the drive side roller race almost always comes
loose
in the early case, either from flywheels shifting out of line a little,
or racing abuse).
More metal in the front end of the primary
chaincase
so that if the chain breaks it won't take the casting out. Bill
Hoddinot
8/13/03
First set of Die Cast Cases is reported to be #9972,
although
some sand cast cases carry a later serial number.
Engine Lubrication
mods:
When
Herve Hamon visited with me he described how he used a small Honda pump
located within the timing chest and driven off the big idler, sited
just
below the breather pinion I think ? This to furnish
immediate
oil to the cam lobes on start up. It drew its oil supply through a
small
pipe taken back into the scavange gully where oil is always left pooled
upon stopping the motor. No more dry lobes or followers. Keeping
the valve springs nicely oil wetted will reduce a big source of rubbing
friction and heat, and a move to single spring technology an even
smarter
move. Flowing more oil through the upper head inner surfaces
should
allow a higher compression ratio tolerated w/o bringing on
detonation.
The old scheme of knife edging the lower edges of the piston to skim
off
oil more effectively - this thrown then up beneath the crown and on the
pin and bosses is still a good trick . The big end eyes can be drilled
through to project oil upwards for cooling the piston underside
too.
Sid 3/2/03
Oil Pump:
It takes 195 revs to pass one cubic inch, therefore 54015 revs to pass
one gallon. These figures now equate with Glyns in as much as one pint
flows in 1.69 minutes at 4000 rpm. So my calculations and
Glyn`s
are the same, 13.5 minutes at 4000 rpm or 27 minutes at 2000 to pass
one
gallon. So now you know why you should be taking at least 50 miles to
warm
up the engine. Trevor 3/2/03
I have fitted several sets of Megacycle
cams both MKI and MKII. I never have
compared
them in a given engine with any other cams but they seem to be
comparable
in performance to their Vincent counterparts (MKI and MKII). In my
opinion
they are superior in two ways: 1) They are definitely quieter (because
of modern quieting ramps) and therefore will probably last longer and
2)
they come with timing specs specified at .050" lift which is easier to
obtain an accurate adjustment if necessary. I have a set of MKI's in my
Touring Rapide with over 60,000 miles on them without any sign of wear.
The lobe centers are slightly different than stock at 97 degrees intake
and exhaust. MKI's are 30/44 and 44/30 timing specs with the MKII's at
37/51 and 51/37. Lifts are about .340 and .385" for MKI's and MKII's
respectively.
Just happen to be close to the source if you need more info. or would
like
to get a set. Dave Molloy 1/23/03
Timing Card information provided by Megacycle
for Mark II Vincent Cams:
Timing at .050" lift at valve. Timing
checked
with Zero Clearance. Cam Number 554x2 (Mark II)
Intake
Exhaust
Open:
37
BTC
51
BBC
Close:
51
ABC
37
ATC
Valve Lift:
.365"
.365"
Duration:
268
Deg.
268
Deg.
Lobe Center: 97
Deg.
97 Deg.
Lash (cold):
.001"-.003"
.001"-.003"
Megacycle Phone: 415- 472-3195 or FAX: 415-
472-1497.
Address: 90 Mitchell Boulevard, San Rafael, California 94903.
They
have no email address. Ask for Barbara in the sales department or
for Jim Dour to answer any technical questions. George Missbach Jr.
1/23/03
Cylinder Liners/Muffs:
Only rarely have we trusted the reuse of cylinder assemblies without
fully
servicing them. On the vast majority the liners were seperated
from
their alloy muffs. Most finned muffs are found to be somewhat
distorted
and giving evidence of the crushing forces they must live with, often
tilted
and of unequal heights. Large precision expanding mandrels - one
each end - allow them to be held and spun on their true centers
while
tops and bottoms are trued to the bore center and recut to equal
heights.
Then the bores, always showing high and low areas plus deposits of
burnt
oil - this evidence of gaps existing when running - are carefully taken
out just enough to restore straight surfaces without this island effect.
The upper liner recess is recut as new. Then
new
liners - usually 40 thou OS pieces - are gripped in the mandrels
and the OD is turned down with a fine cut to the desired size - 6
thou greater than the new muff bore, this just over the distance
covered
by its muff. Beneath that the projecting lower portion is taken
down
to a firm hand press fit in its upper cylinder register mouth, and
marked
for that position, front or rear. After being cleaned carefully this
liner
is wed to its muff under the press while
nicely heated - the sleeve being cold. Allowed
to cool fully under the press it is removed and examined at the upper
end
to ascertain that the flange is indeed fully home after cooling. If not
then the heating and press is repeated to acheve that aim. The process
is repeated for its mate. The drilling site and cupping / milling away
of the rear thrust face for catchment is done Only after being sure
that
the hole will break through Beneath the oil ring land on the piston, it
must not be high enough to force oil in to fill that groove on the
assembled
piston fitted to its rod . If not done correctly that cylinder will
always
run very oily - the scraper ring unable to clear away the excess.
Only a Very thin hard base gasket paper as was
first used will not squeeze down loseing your torque settings. We now
eliminate
that gasket fitting a thin O ring lying in a shallow recess turned into
the lower inner edge of the muff where it meets the liner
surface.
Just a quarter inch wide smear of sealant beyond that is employed, the
rest of the wide alloy faces allowed into full and intimate contact for
increased thermal flow into the cases .
As to the matter of the gap between the upper
faces with the head firmly sitting atop the head - after lapping as
prescribed
in the Works sheets, we usually find a gap width
of around 3 thou. resulting from the grain size differance, the
courser
used on those broader faces having removed more metal. This will
close up hard upon torqueing the head nuts as Irving designed it to do
. With the bottoms of those big nuts and the washer faces smooth and
flat
- use a fine oil stone - and lightly oiled the procedure is to tiguten
criss-cross in several small stages up to a figure of No More than 30
to
32 ft. lbs. Leave sit overnite to settle out and repeat to that
same
figure . For the reasons dig out my piece called " Demon Tweak",
its in Forty Years On " and was fully to Irvings acceptance.
Simply
stated - beyond that figure removes the natural stretch needed within
the
cylinder long studs, this allowing growth of
the alloy column during the full heat of operation, with out distorting
the muff or pulling down the cylinder head internal structure causing
loss
of allignment between top to bottom guides leading to valve leakage and
burning, and rapid stem/guide wear. The shop proceidure described
is very time consuming and thus costly, but there is no other method of
ensuring correct top half function when hot, all necessary for a fast
Vincent.
S.M. Biberman 1/13/03
Cylinder Liners:
I had the same feeling as Tony Maughan. I always thought (and still do)
that Vincents got it wrong. The fact is that the two bores (in cases)
are
not split in the center and thus you cannot put even pressure around
the
liner! When tightening up in the manner the works favoured you simply
put
a depression on the liner (front right/back left) Temperature
differencies
are there as well between muff and cases. My muffs went on the lathe
and
were cleaned out to make them round again. Faces were cleaned up as
well.
I turned two oversize liners out of a spuncast tube (about 50 years
old).
Got this tip from "Mavro" - a once famous Indian tuner who broke
many records and made all parts needed for the engine himself. The
spuncast
tube was very strong to turn and till now does not show any wear - and
cheap as well - on the local scrapyard I paid 5 USD for half a
meter!
The lower part of liners was turned slightly smaller for easy fitment -
just falls into the bolted up cases. After more than three years of
riding
and racing everything is perfect and I see no need to grip the lower
part
of liners. If muffs are machined correctly and everything is square and
even - why should a liner turn in the muff then? There is no rotating
movement
- only up and down.You may add a grubscrew for your personal worries
but
I think this is only a point where the liner could start to crack.
Hartmut
1/9/03
The interference fit
of
liners can be affected by the material
used, 6 thou is the norm for your average Vincent liner made from
honeycomb,
4 thou for the muffs made from real material. As for the fit in
the
case, you have to consider that when material expands, it expands from
the centreline of its mass, therefore a hole will get smaller initially
until the temperature gets
high enough for the hole to grow larger. So any
liner gripped by the case will have the tendency to close down on the
piston
clearance. Also the studs have a story to tell , and if you look
at any piston that has seized, you might find that the seizure marks
correspond
with the studs. This would be due to the studs taking away the heat
from
around the hole, and not
allowing the aluminium to expand so fast at that
point. All this has been found on test at the Anglo/French consortium
works.
So clearance is a definite requirement between
liner and case. You will notice that this will explain Toms experiences.
And if the muff /head joint is correctly ground
in , how can the liner possibly turn? Trevor 1/9/03
Cylinder Liners: From my readings
when I first built my Shadow in during '79 through '81, the intention
by
Vincent was for the crankcase to actually grip the lower section of the
liner. The first set of liners I installed were sized to fit in
this
manner. In 1989, during a top-end rebuild, I went with the new (then)
low-clearance
pistons and a new set of Tony Maughan's liners which turned out to be
an
easy, almost sloppy, slide fit into the assembled (and bolted-up)
crankcase. I was completely aghast and called Tony who stated
this
loose fit was intentional. Tony explained that the grip of the
crankcase
actually distorted the liner, so he purposely turned the lower outer
section
of his liners undersize.
At that point, my concern was the amount of interference fit between
the liner and my muffs which I feared was less than desirable.
With
the intention of locking the liner against rotation, I got the idea to
drill and tap a single hole in the rear base of each muff in which I
installed
a 1/4" socket (allen) screw which fit into a mating 1/4" diameter
impression
ground into the liner. I just barely snugged the screw in place
using
blue Loctite. So far, I don't believe the liners have
turned.
Russ Williams 1/9/03
To avoid cross
threading your exhaust nuts, the
following
should certainly assist you in re-assembly.
1. With the exhaust nuts
completely
backed off, start the nut and note which fin is at say, 12:00 o'clock.
Mark the fin with a felt tip. Do it again, re-start the nut and notice
the same fin should be in the same place.
2. Figure out a permanent
mark on a particular fin that you will recognize next time you
re-assemble
the system. Even if you are by the side of the road, in the dark with a
flashlight, you will Know that the fin with your little file mark in it
goes at 12:00 to start the nut. Carl Hungness 12/10/02
Tapered exhaust nuts:
I stretch mine over a well greased tapered thick wall tube a bit at a
time
until the nut is a snug fit in the
head. A heavy duty vice is all that is required. Peter Bell
12/10/02
Primary Chain Breakage: A
twenty five thou movement of the engine sprocket, would mean about 2
(two)
thou of movement of the chain at the dynamo sprocket. The width of the
link inside the plates is on a good quality chain .228" on
an inferior chain .234" . That difference is
explained by the thinner sideplates used and the poor quality of the
assembly.
The width of the dynamo sprocket is 5/32" (.156" -.010) , so as you can
see a lot of side clearance there. So as you can see plenty to overcome
a sideways movement of two thou. BUT there is also float on the clutch
sprocket, which is why there must be enough side play between the
dynamo
sprocket, which is in a fixed position, and the chain that can move
sideways.
This clearance should be checked with the chain sprocket being moved to
its extreme positions, to ensure that the sprocket is central to the
movement.
I think that it is failure to do just that , that is the cause of many
chain breakage's. Side wear on dynamo sprocket teeth have shown that to
be so. But , Sid does have a problem point with the wear on the engine
sprocket and the ball bearing that it abuts to. I put this down to the
fact that the radius on the shaft entry is now greater than it used to
be, and some bearing manufacturers use a universal inner ring that
allows
for the fitting of a seal, consequently the diameter of the face is
smaller.
Japanese manufacturers seem more guilty of this. What it means to your
sprocket is that only half the available surface is used to support,
and
that's just not enough to stop wear occurring. My modification is
to make a new PD2 in the
form of a top hat, with the brim against the
bearing, and machining off the internal boss on the sprocket. Tests
have
shown that this works, but the sprocket will have to be re- case
hardened
, to replace the case where machining has taken place.
Trevor Southwell 11/16/02
Valves:
For better results the exhaust wants to be 2mm smaller in diameter, and
the inlet 2-3mm larger. Around 3-4 BHP gained by doing only that.
Trevor
Southwell 9/12/02
Valves:
I have done extensive flow testing of Terry's big port head. As
supplied:
intake flows 108cfm at 10" test pressure. 1.800" valve at .550" lift.
35mm
port. After reworking: 156cfm, 1.845" valve .550" lift. 38mm
port.
Exhaust started at about 85cfm with 1.670" valve at 480" lift.
After
reworking: 144cfm, 1.630" valve, .480" lift. How much power do
you
want? More flow, more potential HP. Small valves/high lift or big
valves/low lift. I think that Vincents theory was large
valve
with low lift. This allows the end pivot follower to live a little
longer.
I will settle for .510" intake from .320" lobe and 1.375:1 rocker. For
larger lobe I need to make stronger followers. Race engine will
have
titanium valves with larger margins. Better flow. Maybe the same idea
as
RimFlow? I've moved the valves much closer together and have special
cams
made with 112 degree lobe centers. I am worried about cam and
follower
wear with the spring pressure necessary to control the valve train at
7500-8000rpm.
Anyone know a magic coating? Steve 9/12/02
Valves: The
titanium valve will not work unless you have a mechanical means of
keeping
the collar in place. For a coating try chromium nitriding, a vapour
deposition
process . But what's 8000 rpm going to do to your big end ?
Trevor
9/12/02
Pushrod Tube Seals:
Ahhh, a Series "D", good choice! You can simply take off your petrol
tank,
no silly distance piece to fumble about with as on lesser Vins (B's
&
C's), undo your rocker caps and remove the pushrods. Now loosen the
pushrod
tubes and while wriggling them about, pull the old seals out of the
crankcase.
Go to your nearest/favorite auto supply house and get four each of O
Rings
that look like they will fit, determine which ones fit the best in the
case and around the pushrod tube. After you have rolled one over the
top
of the tube and down to the crankcase, slop some silicone grease on it,
replace the top nut on the pushrod tube loosely and with a blunt edge
force
the O ring into the crankcase, it should be a fairly tight fit and
below
the top of the case if it's properly installed. Do it three more times,
and put everything back together. Fit another "D" breather cap if you
feel
so inclined or even be more radical and stick a PVC valve in the
breath!
er hose(s). John 7/16/02
Pistons:
It is so long since Vins were made that people tend to forget that the
original C.R. was so low. The Rapide was 6.45: 1 and the
Shadow
was 7.3 : 1. The Comet was 6.8: 1 - I'm not quite sure why the
Comet
differed from both the Rapide and Shadow, but pistons were made
in
6.8, 7.3, 8, 9, 11, and 13 to 1.
However,
a standard Twin has enough power for most road use. I was very
friendly
with Ted Hampshire both before and after the close of the Vin
manufacturing.
He always advocated the use of 7.3: 1 for road use, saying
there was no smoother or more enjoyable to drive bike than one set up
in
this way. I know fuels are different today, but here
in England we have to use unleaded, which runs hotter than
leaded.
I have always built my bikes with 7.3: 1 and to this day agree with the
expert opinion of Ted. For all round road use, i.e.
torque
and performance, you can't beat it. Derek J. Peters 7/16/02
Pistons:
If your bike was not vibrating badly and you don´t need to open
the
crankcases, check your piston weight and compare to the new pistons. If
they are lighter there will be no problem (if your crank has the std
factory
balancing). If they are heavier you should machine the pistons to get
back
to the original weight of the old ones. You can remove metal everywhere
but most effective is a reduction in length of the pin. The circlip
grooves
have to be remachined according to the pins length. The inner diameter
of the pin can be opened out to 14,5 mm by grinding and the outer
portion
of the bore can be ground in a taper. It is all very time
consuming
but well worth the effort because otherwise you will not ride the bike
very much.
I got only close to the weight of my 7:3 to 1
pistons with the new 9/1! The sandcast 9/1 were heavier and as
everything
possible was done I was left with an overweight of 28 gr each. After
installing
the 28 gr heavier pistons the vibration was bad and I had to open the
complete
engine for rebalancing ! Once the engine was balanced to the much
better factor of 47 % the bike became smooth again and its a pleasure
to
rev it ! Standard Weight of 7:3 /1 diecast piston is 436 gr complete
with
rings and circlips.This works fine with a works balanced crank because
the diecast piston is already lighter than the std Specialloid at 492
gr!
Fitting the diecasts lifts the balance factor considerably and gives
you
a smooth engine. Hartmut 7/16/02
Timing case spindles:
Get
a good straight edge (a machinists' GOOD straightedge) and measure the
depth of the faces of the area around each spindle from the timing
cover
mating face. Then add the prescribed amount (0.419 to 0.424,
KTB).
Turns some sleeves from whatever material you have available, and sink
the spindles using these as spacers with a washer and nut on the
spindle
end. I suppose one could use a standard steady plate with the
spindles
bolted in for alignment, but I doubt
it is that necessary. Glen Bewley
7/6/02
Spindles:
It seems like individual tubes, cut to length per the stackup of shims,
cams or followers, etc. plus one clearance shim to be removed, would
allow
precise individual insertion. The projection dimensions would be
handy to know, but then the steady plate is pretty flexible; the hollow
oil feed spindles are the critical ones. Rip Tragle horrified The
Faithful some time ago by suggesting that spindles get hammered in to a
heated crankcase; of course, he was using 4340 chrome moly steel
spindles
that should take it. I prefer the light tap myself. Bruse
Metcalf
7/6/02
Irving-Vincent: Infomation
on production of new crankcases and complete engines.
Oil Filter:
Pre-soak your filter in a jar for at least an hour before replacing it
into the machine. You will be surprised just how much oil the darn
thing
holds not to mention how long it will take before the oil flows through
it to the rest of your engine!
Store (new unused oil filters) in a tupper
ware or plastic tight container to keep moth larve out. They bore holes
in wool. 3/6/02
Balancing the Vincent engine:
If the crankshaft is an original unit ( by this I mean the original
conrods
and wheels) it should have conrods of the same forging type (there are
about five different forgings used). These will weigh pretty much the
same
so as long as the wheels are a pair, i.e. they true up well and have
the
same chamfer. You can balance the crank as a single. My method is
as follows : Get the crank running dead true (checked on mainshafts
with
measure clocks near the flywheels and at outer ends), put it in a lathe
and cut flywheels down until both run true - usually they don`t by 0.2
to 0.5 mm .With care you can hang the conrods on a rubberstrip for slow
revving machining. Cover the bigend in fat before machining thus
avoiding
swarf entering the bigend. After turning you have dead true flywheels.
Now the balance: Weigh the little ends (support flywheels on level
surface,
vee blocks are good), rest the conrod little ends horizontal and dead
centre
of your digital scales ( 0.5 grams ). Take the individual and combined
weights for a good average. Add to the little end weights the total
weight
of both pistons, multiply by your chosen balance factor (I would
suggest
a minimum of 45% and depending on your average RPM, i.e. over
3000
up to 50%), and subtract the little end weights. Put the flywheels on
balancing
wheels or straight edges, hang a small container with the calculated
weight
in, and balance. Any small out of balance moments can be corrected
whilst
balancing by varying your placement of balance holes one wheel to the
other.
I would suggest that any holes that may need drilling are done on the
edge
of the wheels, this way they collect no oil or debris. And don`t
forget to wash bigend out and let it dry before balancing! I got
this from Bob Dunn and it works very good! Hartmut 2/2/02
Camshaft:
Measuring lobe separation from the lifter when it is at its highest
point
or points? Put a dial indicator on the valve stems or the tops of
the adjuster and plot the actual lift. This would take into
account
the way the cam nose contacts the follower at different points of
rotation.
Then the lobe separation is measured between the high points of the
lift.
Bruce Metcalf 1/28/02
I am using a Moto
Guzzi
oil filter, it fits in the same place
as the original filter and you can use the standard oil filtercap,
including
the emergency valve. The filter is original for V65, V50 Monza or
V35 Imola, part no. is : UFI 2546500.
Just pull the attached spring off and the special
oilseal out, then find a O-ring of 30 by 5mm and place it
were
the spring was.
I did not invent this myself, Peter Volkers told
me this. jos 1/03/01
Just don't understand why everyone is so bent on
timed breathers. A simple U tube
manometer
will verify how ineffective they are compared to a reed or other
efficient
PCV valve. My Shadow pulls negative 18 inches w.c. between 1000 and
4000rpm.
The trick is a positive sealing and light acting valve. I have not been
able to better the results from a carefully designed reed.
Steve 1/03/02
Pushrod Seal:
The upper seal will work better if the top face of the pushrod
tube
is dead flat. The best way to get the flanged over end of the pushrod
tube
flat is to take the lightest of cuts over the end face in a lathe.
There
is no need to touch the under side of the flange as there is a danger
of
making the flange too thin and fragile if you do. Just remove any sharp
edges with a dead smooth file whilst the tube is spinning in the lathe.
The seal will now work on two machined surfaces - one in the head and
the
newly turned and flat tube end - ET46
Whilst the tube is in the lathe take the
opportunity
to polish the whole outside of the tube with fine emery cloth,
especially
at the bottom end where the tube will enter the crankase seal. Its
amazing
how oil will creep past the finest of scratches so polish all the
scratches
out. No need to worry abought altering the outside diameter of
the
stainless tube but worry about cleaning the lathe of all that emery
dust
properly!
The crankase seal is a poor design! I think a
tight fitting O-ring is a better seal than the standard hydraulic seal
ET104 we have always used. I think the standard seal is distorted
by the close tolerances between the crankase machine recess and the
tube
being too tight, thus preventing the hydraulic design seal from working
as intended. These seals should not be distorted for them to work
properly.
It is better to use an O-ring and oil-resistant sealer around the
outside
just before final assembly. Apply
to the outside only and wipe smooth before the
stuff dries. If you are making new tube nuts ET127 a nice little
modification
is to cut six slots instead of just four this
makes it easier to get the two prongs of the K1 spanner to work in a
confined
area and to enable a nice snug bite on the seals to be maintained. If
you
can, make them in stainless and polish them. Its also a nice mod to put
a thin steel washer between the top of the tube nut and the fibre
washer
to prevent the action of tightening the nut from tearing the
washer.
Andrew Rackstraw 1/03/02
Welding Crankcases:
The "B" case you saw at the Rally was missing a massive amount of
metal.
1 to 1.5 inches from the entire drive side. I knew it would be
impossible
to avoid distortion. The case halves were bolted together and preheated
to 400 to 500 F, checked with temp. crayons. Temp was maintained during
welding with large gas flame. Welding was alternated
side to side and in and out. Slow cooled in
fiberglass
wrap it took an hour before I could touch it. Total distortion was only
.035". Probably could have reduced that by peening the weld. Doing a
major
repair of a "C" case at this time and will try peening. I used 4043 rod
. The repair piece was fashioned from 6061 and joined easily to the
case.
Lots of buffers in 4043. When blended the repair was invisible.
Steve
Hamel 9/26/01
Excessive Valve Adjustment:
Stainless steel is an excellent material for pushrods because of its
work
hardening qualities. I quote from an interview with none other
than
Phil Vincent, in the "Motor Cycle". When asked why he had chosen
stainless steel he replied :- "Stainless steel of certain selected
alloys
forms a very stiff and rigid material which possesses the excellent
quality for pushrod purposes of very rapid work
hardening. Copnsequently we are able to use very light yet stiff
pushrods, which can be left in the "as-machined" condition because the
ball end work hardens within the first few revolutions made by the
engine."
I would suggest that a lot of (valve adjustment) problems have occurred
because over the years pattern parts have
been made of the wrong grade of material.
And pushrods have been used that had damaged ball-ends before they were
fitted. Just like the bad name given to the alloy idlers because
pattern parts were made of the wrong grade of alloy. In the early
fifties these problems were vitually unheard of and Vincents covered
huge
mileages without all the fancy parts that are now
recommended. Pattern parts and ham fisted
D.I.Y. mechanics have caused the myth of Vincent unreliability.
D.J.P.
9/13/01
Cam Follower Wear:
I think that the problem is worsened if the rider allows long warm-up
periods
of the motor just ticking over at a slow idle to warm the oil .
This
cannot be inherently a good practice due to the speed that the
camshafts
are rotating. Not too fast - but way too Slow ! If
ticking
over at 800 rpm, those camshafts are turning over at only
400
revs - half
the speed of the crankshaft . This tends
to cause a juddering and inturrupted motion over the surface of
all
followers and lobes leading to an oil film breakdown . Too slowly
and that wedge of oil seperating the metals at point of contact bleeds
away. Where before all was a sliding motion over that film, now the
pores
and previously rent skins dig in to each other and rapid wear
ensues.
All of this made more possible due to the slow oil pump speed and low
delivery.
The morale of all this is to refrain from long
periods as described. Set a faster idle of 1600 to 1800 -
or
double the
earlier revs. This advances the timing
a bit so burning the pipes less as the flame retreats back into the
chambers.
It is even better to ride your Vincent at a gentle speed to warm all
components
equally and move some air over the exhaust pipes. The
colder weather coming should have you blocking
off those air inlet spaces at the front between fuel tank and the
UFM. This results in a quicker warm up and higher
temperature.
S.M. Biberman 9/13/01
Oil Pump Removal:
I made up a slide hammer type tool that I can either screw a 5/16 BSF
bolt
into (ET109/3) and use it to gently tap the sleeve into place, or
pull
it out, plus I can use it for timing chest spindles also. You do
realize
the two start worm and plunger are a pair and not to be used half and
half
with a regular pump? There is NO advantage to using a two start pump on
a road bike and I learned (the hard way) It'll just push oil out your
filler
cap if you're going very fast and make a hell of a mess...
John
(mercury crest) 05/29/01
Stud Removal:Trevor
Southwell proferred that the stud had been chemically coated for
oiltightness.
So while at NAPA
(North American Parts Association, or some such,
a large parts chain here in the states) looking for the stud removal
tool,
I picked up some PB Blaster. Now, if you've never used this
stuff,
go buy some NOW. It is absolutely the best penetrating oil I've
ever
used, and very few engine builders around here would be without
it.
I had given (loaned) my can to a friend, so was out. However, I
sprayed
the stud, heated the lot, and applied torque to the stud remover, and
out
she came. Glenn Bewley 05/24/01
Head Bolt Removal: Don't
try forcing that rear timing side head bolt too much. It could
well
be held by the rear cam-follower spindle poking into it. If
this is the case you could well do serious damage by trying to force it
out. If
there is any doubt about this, it would be wise
to remove the rear cam-follower spindle before trying again. If
all
the other head bolts came out without a lot of trouble, this is almost
certainly your problem. D.J.P. 05/16/01
Valve Seats: Ampco
45 works for us at a fitting interferance in the head of
1.5
thou, and the stem to guide inner bore clearance is inlets - 2 thou and
exhausts -3 thou. Be sure to make up double diameter pilots
running
in both top and bottom guides to cut the seats dead concentric
and
true to both upper and lower guide bores. We machine up a third bore to
assist with final reaming. This in the form of a top inspection cap in
mild steel having a central boss that is bored to act as a
3rd
inline fixture for stability while doing all of this critical work. We
cut a 3 angle cut on the seats with sharpely defined edges twix all as
an aid to air flow and power. Grinding in is barely needed for
sealing
when all is done to high standards. Old and even new valves often
need truing to achieve zero run-out when the valve is spun and
must
be corrected for consistant valve sealing and compression readings,
thus
strong running and long life. Sid 05/06/01
Engine Disassembly Organizer:
When
I took apart my motor last winter, I kept my cams & shims separated
by putting ~5" x 1/4" dowels into a 2x4, one dowel per cam (or
follower)
and shim group. I did the same with my head nuts and washers,
which
I have miked and mixed to be equal heights. To have the engine
studs
organized, I copied the drawing from the spares list, enlarged to suit
and glued it to a piece of masonite that was drilled for the
studs
at the place on the motor they belong. A couple of 2x4 blocks
held
it up in the air so that it wasn't too top heavy. Bruce
Metcalf
04/19/01
The easiest way to find
T.D.C. is like Carl said with a plug
stop
screwed into the plug hole, but the most accurate way to use it is
different
to the way described by Carl.
The easiest way to make a
stop is to find one of the old type plugs which unscrew to take
apart.
A hexagon bolt of convenient size can be pushed down through the centre
of the plug and the locking ring used to retain it.
Then having screwed the stop
into the plug hole, set up a timing disc, using a tapered mandrel
entered
into the timing end of the crankshaft. (Note you only need remove the
quill
to do this) Then gently rotate the engine forward until it is
stopped
by the plug stop. Note the setting on the timing disc. Then
gently rotate the engine backwards until it once again hits the stop.
Again
note the setting on the timing disc. Having then removed the plug
stop, T.D.C. is exactly half way between the two readings you have
taken.
It is not difficult to do each cylinder in turn in this manner.
You
can then see if the theoretical settings for your 50 degree twin are
accurate.
I've always found them to be fairly accurate.
This way of doing it is
absolutely
foolproof and 100% accurate. How you then time your ignition is
entirely
up to you, whether it be cigarette paper, light, strobe etc. I
personally
favour using the information obtained to use a strobe as I use
electronic
ignition and the exact moment of sparking is difficult to ascertain
using
any other method. DJP 04/18/01
If you are not proposing to use your Vincent for speed
events, then changing to crank-pins
without
nuts is a waste of time and
money.
Certainly people like John Renwick and Roy Robertson use this type of
pin,
but they use their own constructed flywheels which are much wider than
standard ones. This is possible because of the missing nut.
However, very large interference fits have to be used and special
equipment
is necessary to line them up. They also use cranks which are cut
away for about two thirds of the diameter. Fitting this type of
pin
to standard flywheels would result in a weaker set- up than the
standard
one with nuts. It is however possible to use a larger crank-pin
with
nuts, which produces satisfactory results and was certainly
widely
used in racing before the advent of the newer designs. If you
only
intend to use your Vincent for road work you would be better off with a
properly balanced and lined up standard assembly. D.J.P.
03/24/01
While I said that the amount of endplay before
tightening
the engine sprocket nut
did not really matter, I think that 1/8" does seem excessive. The
endfloat
can increase if a loose main bearing inner has worn away the bosses on
the flywheel. It is some times necessary to fit shims between the
bearing inner and the flywheels to rectify this fault. I think
that
after tightening the engine sprocket nut and ensuring there is no end
play,
you should check the position of the conrods in relation to the
bores.
They should be central and if they are not you will need to shim the
drive
side bearing as described. I am assuming that the drive
side
bearings have been correctly installed with the necessary circlips (ET
125) and spacer (ET19). D.J.P. 03/24/01
I just finished a Suzuki
clutch conversion a few months ago
using
the Overlander kit. A few observations:
1. Be ready to spend a few nights in
front
of the lathe! Virtually all of the finish dimensions had to be
cut,
both on the adapters and the Suz clutch. Took more cutting to get
it to fit inside the cover. Also neccesary to have a spare
mainshaft
or something around with the correct splines to use as a mandrel, as
everything
depends on the splines for concentricity.
2. I am running it dry, so far. I
started out using only 3 of the six springs, but with slight
slippage.
I now am using all six but with about .060 shim washers to lighten them
up. Clutch pull is light.
3. It engages rather rapidly, within
about
1/4 of the lever travel. Takes some getting used to. I may
try oil in there to see if it softens it up any, and may change the
lever
ratio. Paul Zell 03/09/01
Suzuki clutches
will only run for about 500 miles DRY. They MUST be wet. So throw
away all the oil seals, and drill a few holes above and below the
clutch
into the primary. Trevor 03/09/01
Engine breathers:
The
only way that makes sense to me is a good PCV valve, the goal being
negative
pressure in the crank case. It is well known in the Hi Perf world that
positive pressure in the crank case is not helpful. Not finding
anything
in the auto industry that satisfies, I decided a reed valve would
provide
the lightest, fastest action. Jap bikes have used them for years.
Modified
a four petal intake reed assembly from an old Yamaha single to fit a
small
cylindrical housing. Also got to thinking about oil separation and went
to a lot of trouble to build a system that would allow oil mist in the
vent to condense and drain back where it came from. A primary
consideration
was for the installation to be inconspicuous. Once installed it needed
scientific testing. Contacted some friends at Aerospace Engineering at
the Uof M who provided a dynamic test system using a piezo transducer,
A/D interface, and laptop.This system samples 1000 times/sec. To verify
data we also set up a seven foot tall U-tube water manometer. Readings
were taken at 1,2,3, and 4 thousand RPM. The stock breather made minus
9 inches @ 1000, minus 3" @2000, zero @3000, and plus 3" @ 4000. The
reed
valve gave minus 18" @1000, minus 10" @2000, minus 19" @3000, and minus
19" @ 4000. Cannot explain the jump at 2000 RPM but over all the
results
are impressive! During the tests it was apparent that the c/case
evacuated
very quickly to a relative negative pressure, after which very little
air
moved through the system. This allows venting through small diameter
hoses.
3/8" ID is enough. Sorry to say it but the elephant trunk is hideous
and
really spoils the view. Road test was next. Several runs at 75 to 100
MPH
sustained and a couple of 50 to 100 mile rides proved the system. Total
oil separation from the breather, no milky residue, just a few drops of
clear water.
Engine is dry. Working to condense the system
into a package that is easily hidden and will amaze your friends.
Steve Hamel 02/27/01
Engine Breather:
Steve
- Since you were sampling at 1 kHz you should have seen some
substantial
varations in crankcase pressure. However you mention only (I
assume)
average pressures. Please fill us in in the details of how
crankcase
pressure varies with piston travel. What is the
availability
of raw data, tables or charts? Doug Wood 02/27/01
Engine Breather:
Pressure
readings are averaged. Efficiency of valve affects ratio of plus to
minus.
The better the seal on the up stroke, the fewer air molecules are left
to be compressed on the down stroke. Interesting that at 1000 and
3000RPM
the dynamic graph shows almost entirely negative during both up and
down
stroke. At 2000 and 4000 RPM the range is plus 12" on the down stroke
to
minus 32" on the up stroke. Maybe a resonance in the reed. The
raw
data resides in Argentina with the engineer who built the
transducer. I'll try to get it as the graphs are four color and the
yellow just won't copy or scan worth a darn.
Paul Zell, your gulp valve is an interesting device. I've had one
apart
and you are right in that they are a bit stiff but effective as you
have
proven. A U-tube manometer is simple to make and use. 8 to 10 feet of
clear
1/4 or 5/16" hose stuck to a board. Half full of water and you're set.
Rig an old tappet cover with a barb fitting and connect to one end of
the
tube. Fun to watch it react to different systems and conditions. the
tube
and water damp the oscillations and give a nice visual average
indication
of c/case pressures.
John C. it would be interesting to know if your system stays
negative
all the way up the rev range. Steve
Hamel 02/27/01
Engine Breather: All
I
did
was follow Irving's advice, except I went a bit further in
increasing
the sectional area by drilling out the spindle and enlarging the
fitting
in the crankcase. Because of the increased chamfer and opening of
the breather slot, the duration of opening was necesarily increased
somewhat.
At idle a puddle of oil about 3/4" long would enter the clear breather
hose; above idle it would draw back into the engine, indicating a
slight
negative pressure at any speed above idle. No oil separator
needed,
no valve needed. I'm happy. It's only fair to admit
that
I "read the directions" only after several years of pursuing perfection
through developing my own systems of PCV valves, oil separators,
etc.
John Caraway 02/27/01
Colin Taylor of Lincs phone #
079800
90533 is selling Lightning Exhaust
Pipes
for 195 pounds, either over and under or staggered at 45
deg.Whilst
they look good, the standard diameter at the port appears to be too
long,
this is critical to their extractive effect. It should increase in
diameter
just past the exhaust pipe nut. dimensions if I remember
correctly
are in Tuning for Speed. You will find that you will have to jet-up,
and
alter the slide cut away,as well buying ear defenders, I would
also
like to know if these have tested on a dynamometer. Ken
Tidswell
02/13/01
Engine Breather:
The trick is to have it as the sole breather and quite large in
internal
bore say 3 /4 " hose on to a right angle elbow in alloy, pointing
upwards
at one o'clock. A large hose releasing thusly will vent in a
slow,
gentle puff too low a velocity to pick-up and carry out any oil. A
small
bore inside diameter hose will vent in much quicker velocity blasts
which
will carry out oil with it. Sid 02/08/01
Engine Balance Factor:
The
reciprocating weight is the weight of the small end lying at rest on a
scale, with the mainshaft and crank pin in a horizontal plane. This is
then added to the combines weights of the Piston : Rings : Gudgeon pin
and circlips. So given all that, here`s a simple way to check out
the assy.
Select the balance figure you require (X) .
Therefore
X % of the total weight of the above is the figure to apply to the
following
experiment.
1. Place the assembled (minus piston) crank on
a set of knife edges.
2. The assy. should then fall into a position
that puts the crank pin directly above the mainshaft.
3. If they do not, this means that the balance
weights are out of kilter. So that material will have to be removed
until
the aforementioned state is obtained.
4. Then add the weight of the balance factor
( X %) to the small end.
4. Then add the weight of the balance factor (
X % - the weight of the small
end) to the small end. (note:
correction in next comment)
5. Roll crank along knife edges.
6. The crank should then stop in any position
, no matter where the crank pin is.
7. If the crank pin falls to the bottom or rises
to the top , every time time it settles , add some plasticine to the
periphery
of the wheel until it can stop anywhere. The weight of the plasticine
gives
you a good guide of the material either to be removed or added.
Derek
Peters 02/07/01
Correction:
4. Then add the weight of the balance factor
( X % - the weight of the small end) to the small end.
So imagine we want 35% and
the
total weight of the end plus piston etc. is 21 ounces (example
only),
and the small end( reciprocating weight ) is 7 ounces, the weight
to be applied would have to be 35% of 21 ozs == 7.35
....
Now subtract the weight of the small end. .35
ozs
would be the weight required for the experiment. If we apply a
55%
balance figure the weight would have to be 4.55 ozs. These are
imaginary
figures. And all for a static balance. Trevor 02/07/01
Opening up Ports:
The rear head will open out easily to 32mm being careful not to break
into
the lower spring well. Favor more removal elsewhere away from
that
thin spot. Front heads will allow nearer to 1 3/8" and this size
was favored by Amals when I asked
them years ago, and was what We aimed for even
with our 2" inlet valves in our Big Port Works heads. Too large a port
will lose velocity, and the real restriction is the low lift
anyway.
Flow can be boosted by releaving around the back-side of the
inlets,
involving the liner flange and head metal in that near
area.
Sid Biberman 02/05/01
Sid's Hop-up Comments on the
Cylinder and Piston Group: Each
part must be blueprinted and each pair made equal in all important
dimensions.
Before the cylinder liners are fitted to the muffs, ensure both muffs
are
the same height, top and bottom parallel, and at right angles to the
central
bore. Prep the new oversize liners so their outer faces and their
freshly bored and honed inside walls are both dead straight and
parallel.
The new outside liner faces offer nicely finished surfaces for a
.006" tight press fit in the cylinder muffs. The top recess in
both
muffs should be prepared with the same precise eye. The liners should
be
properly inserted into the muffs and held secure until
cooled.
If any gap is allowed under the liner flange, the liner will later drop
and spoil the lapped joint. The oil feed to each rear piston
thrust
face must be correctly sited to emerge below the lowest ring groove. If
the oil feed emerges into the lowest ring groove, it will detrimentally
fill the groove with oil during engine running.
All of the above efforts have been directed
at
maximum rejection of heat and maintanance of good ring seal during
severe
use, all paramount in a racing motor where one expects any chance of
winning.
Of equal importance is the proper fitting of the piston to bore and we
would - even with modern silicone alloys - prefer a skirt
clearance
in a Vincent on the order of 004" rather than risk some picking
up
or outright seizure. My old Rattler ran its old Specialloids at
no
less than .0065" which had grown a full thou. after
the
first run at the lights. These were 12.5:1 compression ratio.
Serious power needs high combustion chamber
heat
and tight crown / head interface for any real squish effect. Prior to
running
the engine, check with clay the actual seperation distances and all
relationships
between components. Check again after the initial running and later
again
after the first race when youth and anger makes fools of us all.
Repeated
examination shows how clearances narrow as the rods fling and valves
float
leaving telltail marks the wise tuner had best keep up with,
removing
metal whereever evidence is left behind.
Vincents run long and full bore often show
scuffing
around the piston pin hole on both sides. The scuffs are signs of
growth
in width across that plane and should be eased by carefull removal of
metal
in the affected areas. Pay attention to any valve contact of the
edges and surface of the cutaway relief in the piston crown.
Contact
in this area may cause serious damage during high-rev valve float
periods,
especially where bigger valves and higher lift cams are employed.
Heavier and broader inlet valves bring on float far easier and must be
watched as springs weaken. Burnt and abused exhaust valves can
show
melting away at their edges from operating at elevated
temperatures.
Sid Biberman 02/01/01
Reducing
the weight of
your Flywheels: Imagine the
completely
assembled fly-wheel /rods assembly sitting on bench in front of you,
its
mainshafts horozontal - left to right - with both rods lying down
sloping
towards and resting on the bench. To each side of the rods one
faces
the edges of the wheels. With a 6 inch machinest ruler and a felt
tip marker {fine point} you draw a mark across both edges the
width
of those wheels. Remove 25 percent of each marked line, this to
be
off the edges nearest the rods, ie. towards the center of the
assembly.
That clean portion of the edge of each wheel will remain untouched
during
the removal process being needed still as the surface from which all
oil
is still to be scraped. The remainder of the marked surface,
75
percent of the original width is to be turned off on an angle outwards
towards the outer face of each wheel. Examine the surface up the
side and find a little drilled hole - must be a Works original locating
index / fixture point. This is used
as the stopping point for your cut, and duplicated on both sides.
The weight of metal removed in this area does NOT affect the balance
yet
is a considerable decrease in mass/inertia allowing the assembly to be
spun up far quicker consuming far less torque power in the process.
Elapsed
time over the quarter mile will take a big cut and as a result the
speed
through the lights can be far higher. S.M. Biberman
02/01/01
Comment
on Sid's Flywheel Mod: On a
twin
flywheel , when one machines a chamfer as you describe. You will remove
more material from the balance weight side, so I think the balance
factor
will be altered. On a Comet this does not happen, the wheel being
parallel
across its diameter. Trevor Southwell 01/02/01
Dipsticks:
There's 80 on your Vincent that will do the job, just cut a spoke to
the
length you require. The length you require is only to be
determined
with the G2 cover off. With the layshaft gears in position, pop in the
dipstick and mark to suit. Ensure you know where the oil level is to be
. I have it so that the largest gear is dipping into the oil at rest,
by
about 3/16 inch. That way you will know that it is doing its job.
Any old dipstick is not the way to go. There are tooo many variables
for
there to be a standard dipstick, that's why they are made adjustable.
So
adjust the one you already have. But if you really do need another, you
must have a broken spoke laying that you can make a new one
from.
Trevor Southwell 02/01/01
Half-time Pinion/ ESA springs:
The system Irving chose which allows for fine lash adjustment between
big
idler and the cam gears and half time pinion is another
cost-be-damned
example of his design ethics. By placing the big idler spindle in a
movable
base allowing it's center to be moved upwards and in an arc, it's lash
with the two cam pinions can be set to fine limits. The altered lash
between
the bottom driving pinion can then be catered to by providing a range
of
these pinions having a difference in their manufacture of 9
choices, both in larger and smaller increments,
by one thousands large or smaller gears. Thats 9 up and 9 down . This
is
an
expensive undertaking for the Maker to accept
as his responsibility but of massive assistance to the owner
wanting
high performance and a quieter timing chest. Happily stateside
Coventry
Spares both stocks most of the alternate sizes and
assists the owner as best he can select the best
pinion for his motor. Were you aware that the Honda 4 cy. K
bike of '69 through '77 offered only the single std. size
crankshaft
bearing shells ? Scratch or score a crank journal and you were
out
of luck. Order a new crankshaft ! Lots of displeased owners
!
If our ESA assemblies are fitted and done-up
carefully,
even the B/C units function well and beautifully for many, many
thousands
of miles. Only recently have we spotted the reason for broken
springs
in some examples, actually 2 reasons. # 1: Many times the
depth
of each spring hole in PD3 /2 varies enough to cause a coil-bound
condition
in a number of those pocketing holes. All must be checked for
drilled
depth and the shorter ones drilled deeper. Also, it is wise to inspect
the mating together for least free to and fro unchecked movement
between
the two cam elements, the PD 3/2 and the lobes on the drive
sprocket
. Each of the alternative mating positions is tried - pressed
together
firmly - and the outer element turned in both directions seeking that
choice
where there is little or no outward thrust - uncontrolled by the spring
pressure. Free movement or coasting will cause rapid cam wear and
noise, roughness at town speeds and also broken springs. The springs
are
to be each greased and popped into its mating depression in
PD 5 during assembly. Removable or Blue loctite allows later
service
w/o severely damaging the hex on PD 7 and a good air driven impact
wrench
-1/2 in. drive and a solid socket is the way to insure both fully home
assembly and later removal with ease.
Assembled to these standards will insure no
spring
breakage and long, smooth, and slick functioning. The Series D pattern
is
somewhat better with more springs, thicker outer
plate and a locking eared washer, all of which is great yet the earlier
faults need be attended to for
greatest
advantage.
A word of warning: The big impact wrench
driven by 90 to100 PSI air in your tank delivers serious twist and can
easily cause problems -as well as work miracles ! The ESA is
carried
on the drive side main shaft which is held tightly within the flywheel
by its interferance fit as well as a Mills pin, Irving's
term
for a rather soft grooved sheer-pin as long used to secure the
propeller
blade to its driving shaft on an outboard motor. Strike a rock and the
pin is cut across and through-saving the Prop but often having one
paddle
home. My warning -- when using the tools described be very wary when
turning
on the nut PD 7.
Reduce the air flow approx. 50 percent,
then lean into the wrench while listening /observing and being sharply
aware that the nut spins up smoothly till it comes to a gradual stop -
ceases to rotate - indicating all pieces are bottomed out against
each other. Don't bang away at it any more ! Dead home
solid
is achieved, and no more torque is to be applied lest you spin the
shaft
in its wheel - sheering that pin ! If a couple of drops of
med. loctite has been spread round the threads which were first made
clean
of oil, then All is Secure. Assembly is greatly eased by sliding
out towards you the splined sleeve PD4 allowing all components to go
home,
especially disc PD5 must accept those splnes on PD4 . Sid
Biberman
01/17/01
If you have a mill it is relatively easy to check the
bearing alignment of a set of cases.
Using
the
timing chest face as your datum, clamp the timing side half down
onto the mill table. Then having mounted a dial indicator in the
mill spindle you need to clock both timing side bearing housing faces
to
centralise the spindle and ensure that the two bearing housings are
concentric
and in line. You may have to pack up the timing case face to
attain
this situation if there is any damage to the timing chest face.
You
then clamp the mill table and place the drive side crankcase half onto
the lower case using the dowels to locate it. You then clock both
bearing housings in the top case half and ideally they should both be
in
line and concentic to the spindle. It is also just as important
to
traverse the dial indicator up and down the muff clamping faces to
ensure
that your barrels are going to be square to the crank shaft. If
everything
is not true to within about .0005" it would pay to consider having the
bearing housings rebored and bushed with aluminium bronze. Derek
Peters 12/18/00
If you are not proposing to use your Vincent for speed
events, then changing to crank-pins
without
nuts is a waste of time and
money.
Certainly people like John Renwick and Roy Robertson use this type of
pin,
but they use their own constructed flywheels which are much wider than
standard ones. This is possible because of the missing nut.
However, very large interference fits have to be used and special
equipment
is necessary to line them up. They also use cranks which are cut
away for about two thirds of the diameter. Fitting this type of
pin
to standard flywheels would result in a weaker set- up than the
standard
one with nuts. It is however possible to use a larger crank-pin
with
nuts, which produces satisfactory results and was certainly
widely
used in racing before the advent of the newer designs. If you
only
intend to use your Vincent for road work you would be better off with a
properly balanced and lined up standard assembly. Derek
Peters
12/18/00
Replacing parts:
Like the surgeon's inciscion, there is a liability with each change. A
main bearing outer race, when removed always leaves a looser fit for
the
next bearing. A crankpin, once removed will soon require an OS pin and
another machining operation to bring it (hopefully) within
tolerance.Valve
seats removed for new seats seem to be more likely to drop their seats
in the future. Do it cause you really gotta do it. Sometimes its well
enough
left alone. Somer Hooker 12/05/00
Valve Guides:
We make our own lower guides from a very hard and dense wrought
bronze
in modern usage called Ampco 45 .
Thus
we can clean up the bore in a heavily worn head and produce an oversize
OD guide giving the exact fit desired. While at it we cut the
groove
for the Viton O ring for oil control down the stem , this positioned
just
below the flange for greater strength during
insertion.
We prefer this location rather than set into the bottom side of the
lock-ring
.
Alignment run-out often sees the threaded ring
off to one side so that the fragile O ring is then off center to the
stem.
Many valves seen here both used and new when checked are bent quite a
bit,
and even show poor quality manufacture in that
there is visable runout of valve head to its
stem, thus affecting the concentricity between seating area and it's
stem,
none of which is good for consistant sealing and performance.
Poor
service to valve and seat rings will result in blurred and rounded
seat/valve
faces, which reduces efficient breathing and power. We do a
3 angle treatment actually cutting with 3 seperate cutters set at
3 different angles. The sharply defined edges between each giving a
precisely
defined seat and width. The sharp edges contribute to much
greater
flow across the sealing surface when the mating face of the valve is
treated
in a similar fashion. The greater the flow, the greater the volumetric
efficiency.
None of the above is possible without proper
piloting
on double diameter pilots riding in both top and bottom guides to assure
positioning of the cutters. We go even one step
further by adding a third support. This a precision steel cap
modeled
on a inspection cap but carrying another central boss in excess
of
one quarter inch thick bored to align with the other two guides
below.
Each top guide is selectively positioned for free stem movement and
then
punch-marked to allow it to be assembled later where earlier it was
best
located. All of this done to ensure consistant sealing at each valve as
well as contrubuting to high power and long
life.
Sid Biberman 12/05/00
Rocker Arm Facing:
Place a pad of abrasive on the collar, use double sided tape. Assemble
the rocker and fit locating screw. Rotate valve easing it up and down
at
the same time, until you have ground down the ears on the rocker to an
even
shape on both. You will find that the resultant
curve on the faces is almost flat. So why the big curve on the face
from
new I do not know. They tend to dig into the collar and
indent.
Trevor 12/05/00
Con-Rods:
The most efficient and least damaging method of removing chrome
plating
is to have a competent Plater reverse the process. Afterwards you
should
heat soak the rods in an oven for 4 hours at 350 to 375 degrees F.
Re-polish
along the flanks and around both eyes, especially where they
blend
in to the flanks . I would suggest they be Magnifluxed, and finally
shot-peened
at a local Hot-Rod engine builder, the eyes blanked off with
steel
discs to eliminate exposure to their ID's . We often
see tiny
cracks rediating outwards around the edges of
the bigend eyes -- usually where a caged roller bearing has been
used . These tiny beginning cracks dont seem to grow longer in
further
use, nor cause failure. Recently we have used several pairs
of
Terry Prince's lovely con-rods and they appear superbly designed and
manufactured,
and the most identical of all yet examined.
Sid Biberman 11/26/00
To get rid of
Hydrogen embrittlement, soak the
plated
item in an oil bath which is maintained at 177 degs. John 11/26/00
Distorted Con Rods:
Turn your motor over with the heads off . This will show if the piston
"walks" to one side (left or right), easy to see by eye . Arthur
Farrow 11/26/00
The weight of a freshly completedVincent
engine is 199 lbs - Including
the
magneto and Miller generator as well as pair of carbs and inlet
manifolds.
Simply weigh those items and subtract from the stated total . Sid
Biberman
11/22/00
Wear on big-ends:
These results seem to be based on experience in more modern times when
caged roller bearings have been used and after much work has been
carried out over the years since our machines were made. Undoubtedly
the
treatment meted out to Vincents over the years have resulted in very
false
impressions being gained in the aftermath of very poor
maintenance.
Back in 1951 Tony Rose carried out the 100000 mile test of a
standard
Black Shadow and the wear on the big-ends, when finally stripped, was
extremely
small. In fact the big-end outer rings wear was a maximum of
.0004
inch and the crankpin roller tracks maximum wear was.0003 inch while
the
rollers were so little worn that no comment was passed on them.
As
far as the Works were concerned the big-end was just nicely run
in.
The things to be noted about this are that the engine was standard and
the oil (Filtrate with Colloidal Graphite) was changed every 1000
miles.
Due to owners wanting to rev their machines the caged big end has now
become
the main one in use. This does undoubtedly not have the
life
of the crowded roller big end used at low revs, but is much safer if
you
drive your machine fast. However, even with this type of big end
the advice of Phil Vincent given to Tony at the start of his test
stands
good. He was quite happy the engine would do the 100000
miles
without needing major replacement as long as the revs were kept down to
5000 and the oil was changed every 1000 miles. There are not many
owners who can say they have any experience of this kind of mileage,
but
one thing I would certainly not do is strip down a big-end at 30000
miles
to fit new rollers to worn components. Only if you are prepared
to
hone out the big-end outer bush and grind the crank pin before fitting
oversized rollers is this recommended engineering practice. And
if
a big-end is sufficiently worn for this to be necessary then it is time
to fit a new bearing.
Can Aircraft Gas be used in
Vincents:
Some years ago John Bradshaw? wrote an article in MPH re. Burnt Ex
valves
in his vintage aircraft - A Sea Fury powered by a Bristol Centaurus, I
believe. His information was that leaded fuel does infact burn more
slowly
and was still burning when the Ex valve started to open, so burnt
valves.
The advice he was given was to run this engine on 87 octain aviation
fuel.
This he did and no more problems. This is confirmed by the fact that at
a French Rally held at La Fait Alais all the vintage aircraft bore the
legend " 87 Octain only" on their engine cowlings. Wm. Clive
Richards
11/22/00
I wondered a while back how in
the
world Mr. Higgins' fix for head warpage,
which involved shims under the nuts (as read) on the heads would
help.
Easy enough, it occurred to me the other day, and was confirmed by the
man himself today. The shims are between the head and muff,
taking
up the space normally left when doing the narrow face/broad face
lapping
in of the surfaces. Shims of a thou or a thou and a half, held by
both the head and the liner flange nipping down on them.
Glenn Bewley 11/22/00
At about 40,000 miles the
rollers
in your big end,
if you`ve looked after it and warmed it up before thrashing, will be
half
a thou under. The pin and eye should still be OK. But then it starts to
go downhill faster. Sure you can make it go on longer, but the
final
wreckage is a lot greater, with having to replace everything. So tear
down
after 40,000 and re-roller, and this gives you a good chance to make
sure
all is OK elsewhere. Trevor Southwell 11/21/00
Valve Guide Installation:
1 Put head on fixture at the correct angle
for the valve, using the four counterbored locating holes, as was
originally
used.
2 Clock in upper guide register.
3 Bore out for valve guide. And maybe reclaim
the lockring thread if its buggered.
4 Heat up and fit new guide, and seats if you
are doing these as well.
5 Replace on fixture, CHECK that the upper guide
register in is the same place. And I will tell you now, that it will
NOT
be.
6 Bore out the guide to its required size.
7 Machine the upper guide recess to ensure that
the face is square to the guide. If necessary you might have to
oversize
the upper guide if the the recess is out of round.
8 Refit lockring, heat up and tighten.
Some comments.
Every time you heat up a head , and recheck it
on the fixture . It never comes back the same. It`s walking ALL the
time.
I consider that this is also happening in use, especially the front
cylinder
being the frame. What with the honeycomb muffs and all that. I
think
that this is one of the reasons for the front push rods always (nearly)
wanting adjustment. A big problem nowadays with heads is that over the
years they have been got at , by the go faster, I must make the holes
larger,
rider. This person believes he can make the plot more efficient, when
in
fact he is destroying the original design. Valve guides no longer have
the supporting material around the part where the guide sticks out into
the port, so that when you place a guide in place, on cooling it will
tilt
away from where it should be. SO NEVER try to use a guide that is a
finished
size. NO CHANCE.
I have found out that the face of the
upper
guide is not always true with guide, especially front exhausts.
Doing
it this way could lead to the seats having to be miles out to keep in
line.
So I now ignore that face and machine it last, this way I now know
where
it is. My methods have evolved over the years, some 300 or more
heads
down the road.
PS. I have never found two heads the
same.
Exhaust ports as much as a quarter on an inch out of position, varying
in depth by 3/16 " . However did you expect exhaust pipes to fit? Valve
guides anywhere but in the correct position , at least to the factory
drawing. The least said about rocker
tunnels,
the better.
Trevor Southwell 11/13/00
Tightening the rocker
feed bolts. If you do this with all
the
valve gear in place you can finger tighten the rocker feed bolts, and
then
roll over the engine so that the bush is under load, that is pushing it
against the underside of the rocker tunnel. then
when you tighten the feed bolt you are assured
everything is where it should be. Robert Watson 11/13/00
Erratic Compression:
I have
come
across
these symptoms when an ET35 collar is moving up and down on
the valve stem and occasionall jamming in the up position. To
find
out the only way would be to lift the head. However I think it is
far more likely that you have a valve sticking in it's guide and
this is much easier to solve. Get some upper cylinder
lubricant
(e.g. Redex or Marvel Mystery Oil) in a pressure can and if you can
start
the engine squirt the mixture straight in to the carb mouth while it's
running. If you can't start it then squirt the lubricant through
the plug hole and carb whilst kicking the engine over manually.
Once
you break up the gum which is jamming the valve all should be
O.K.
If this solves your problem make a habit of including a small amount of
upper cylinder lubricant in your petrol to prevent a
reoccurrence.
Derek Peters 11/09/00
Erratic Compression:
With pipes and carb. removed -- and with a length of rubber hose
- each in turn listen with one end held at each exposed port .
With
sparkplug in place slowly listen - while the motor is slowly turned
over.
You WILL hear the air rushing past the leaking valve at one
or the other, ie. at inlet manifold and then the exhaust port .
My
guess? One of two things,-- #1 A chunk of soft carbon
has been caught betwix one or the other valve and seat , or
--#2 One valve has suffered stem to guide scouring /
picking
-up{too tight clearance }. Probably the
exhaust
, and at its lower portion . My suspicion is # 1 .
When
the hiss is pinned down try to soften the clump of carbon by
spraying
through noisy port a hefty squirt of WD-40, several long
bursts
through the port aiming at the seat area and trying to cover the
entire seat- ring . Let it sit and soak one hour
.
Now with that length of hose on your air pressure line and holding the
hose into first the plug hole --blow short - repeated blasts
while
the motor is kicked over. Next blow through inlet
manifold
- hose shoved in right against the valve back-side . While
blasting
air spin over the motor then do the same deeply up the exhaust
port
- while spinning over the motor . If I'm correct - there is
a good chance the crud will be blown away . Replace
plug
and kick over. With luck - and if I'm correct -
compression
will be restored . S.M. Biberman 11/09/00
I had a bad time sealing
the
rear
intake push rod seal on the
rapide
(Mr Woolly Mammoth) despite good braething and no crankcase
pressure.
I made alloy rings with internal o-ring grooves and .000 fit and
locktite.
That did it. You must make each to fit as pushrod tube diameters are
all
over the country for OD. And when you dismantle keep track of each, as
you should do with the pushrods and adjusters, as they have all "worn"
in together. Robert 11/09/00
Just a Quick fix for lower
pushrod
seal carefully dig out the old seal, degrease well and fill
with a bead of black RTV, ie Dow Corning 732 number 110311 Black, if
you
do it carefuly it looks just like the real seal and it
works.
Roger Lord 11/09/00
Timing your Vincent using Rod
Bearing Inserts: When you are running
a highly modified motor (e.g. with nitro) , you don't
exactly
have an owners manual to time in the motor. It will change throughout
the
day anyway. If your motor is too advanced, then the top part of the
(rod)
insert will begin to show more wear as it is fighting the detonation or
"spark knock". I actually learned this from Dave Matson, who uses the
same
technique but only at the end of the year. Later when I saw them
pulling
the inserts out of motors ,I realized what they were doing. If the
bearings
are the same on both sides,your timing is spot on. If the bearing is
wearing
on the bottom, its too far retarded. Somer
Hooker
11/05/00
Timing:
As a nitro burner needs ignition advance ranging from 54 to 60 degrees
before TDC to acheve best results, a gas burner street motor
needs
38 to 39 degrees and a Methanol motor less at
34
to 36 degrees to function at optimum . Thus retarded timing on
the
(Dave Matson) Bonneviile bike is retarded at 48 to 52
degrees.
Sid Biberman 11/05/00
Engine Gaskets:While
attending the Arkansas National meet a few summers back, I spied a
lovely
restored Black Shadow that had a very fine copper line separating the
primary
cover from its attachment, and another on the timing chest. I met the
restorer,
a meticilous man named Dick Busby who also said, "Hell, I quit using
gaskets
a long time ago. I use "Permatex Ultra Cooper."
Further research among my racing engine
builder
friends found some utilizing Hylomar, but the best seemed to like the
very
small tubed, and expensive anerobic Loctite...very, very
sticky.
Consequently I bought the Loctite and among all the leaks I have had on
my Shadow, none have come from utilizing the silicone based
materials....and
I have purchased no gaskets since.
Locktite 518 is very sticky, tends to stay where
applied, and merits consideration. Carl Hungness 11/03/00
After years of trying we finally
sealed a friends DBD34 to oil-tightness
by using Gaskacinch, which is WONDERFUL gasket cement. And worth
the price of admission just for their really cute "mascot" or whatever,
which is an illustration of a young lady which looks as if it should
come
right off of the nose of a B24. Of course, I am a huge fan of
Hylomar
as well, when there is no gasket, and copperkote on copper gaskets.
Glenn Bewley 10/4/00
Location of Oil Holes on Cam
Spindles: Oil holes in any situation
should
always be on the non-load side (opposite the thrust forces). So point
them
at your main bearings. If they were on the load side, the
pressure
would keep the hole shut. So some to avoid this, make the hole into a
slot.
This in turn is a tool to wear away the bush. Trevor
9/29/00
Cam Spindle Oil Holes:
I think the fact that the Vincent uses a low pressure oiling system
makes
the location unimportant. This is backed up by "Vincent-H.R.D.
motorcycles"
published in the "Motor Cycling" Maintenance Series with help given by
Vincent Engineers (Stevenage) Ltd. I quote "Camshafts are mounted
similarly to the followers except that the two spindles are hollow and
have oil holes, the disposition of which is unimportant".
There is no thrust against the oil hole in the
cam spindle for it feeds the oil between the two bushes at each end of
the cam shaft. So I maintain that it doesn't matter one jot where
the oil holes are located around the circumference.
Correction: I completely forgot the
second
oil hole under the inboard bush. Still with a good supply of oil
into the centre of the shaft, I don't think it would cause great
problems
wherever the holes were located. However I'm inclined to agree
with
Sid that it would be better to keep them away from the top
position.
DJ Peters 9/29/00
Lubrication:
... the shearing action of a gearbox is not good for
multiple
"weight" synthetics, which achieve their viscosity range by use of
polymers
(extended molecular strings). BTW in this regard, for any engine,
it is best to use a multi-grade synthetic with
the narrowest possible range--that is, a 20W-40
is likely to be longer lasting than a 5W-40. There is also an
extensive
body of opinion about whether synthetics are the ticket for low
pressure
roller bearing engines (did someone say British bikes--
do I hear Vincent?). I offer no opinion
on that. I'm interested that Honda sells asynthetic for its car
trannies
(MTF) -- and that it is very low viscosity as well.
BTW I think the 90W designation for gear lube
isn't to signify that level of viscosity, but to keep you from using it
in your engine. Its viscosity is probably more like 50W. In both
cars asnd shaftdrive bikes the differential fluid recommended is 90W
mineral
oil, and obviously its primary function there is to deal with shearing
and high load bearing forces without regular, or at least frequent,
changes.
As to the recommended viscosity for vintage
Brit
gearboxes--I think all that matters is the quality of the gearbox
seals.
If you've got felt seals in a trannie that's meant for a mix of grease
and oil (if not grease alone), it would seem that a lubricant with low
viscosity like that recommended for Honda cars (my previous message)
will
find its way out to decorate other parts of the machine--or to the
clutch
or primary chaincase.
I still believe as a general theory that it's
more important to change oil frequently than it is to use any
particular
viscosity or "brand" of oil, or oil from a particular source, be it
beans,
minerals or the laboratory. I have a prejudice only against high
sulphur content oils, because of corrosive damage I've observed as a
necessary
effect of cooldown cycles.
john caraway 8/00
Gearbox-graded oils
EP80/90etc, have better gear meshing breakdown resistance, so the
molecules
stay in grade longer, providing the correct lubrication for the
gears.
20/50 is thinner, and thus has more "fling", so lubricates more of the
gears - but goes out of grade quicker due to the meshing of gears...
I'd
suspect it's best to leave each in the environment it was designed
for!!!
Vincents:- Well, I use EP grades for the
gearbox,
varying dependant season, and straight GP50 for the engine -
Tigger
Aldus 8/00
I believe the
thread size for a (bottoming) die that
will re-cut the threads in my Vincent Series "C" Twin Head
is 1 7/8" x 20 TPI, ...Whitworth..I think it has a 55 thread
degree
angle..and I believe the American counterpart has a 60 degree angle,
but
I have also been told that the American die will work.
Carl
I was once in discussion with Big Phil on this
business
of the stripping of exhaust threads
and he made an interesting comment. He said that it was strange
that
the exhaust nuts seemed to get a taper on them after some time and they
were not tapered when new, he said "why not heat the nuts and push them
over a taper mandrel and restore them back to
the proper un - tapered shape".
I have never had to resort to doing this but
it
does make a bit of sense when you consider the heat the nuts are
working
in and the compression they are under and the relative thin wall of the
nuts.
I have an exhaust thread bottoming Tap, I
bought
the tap from a tool company in Hackensack NJ phone 1-800-342-8665
called
'Tool Importers' should you find their email address would you forward
it to me - thanks
Andrew Rackstraw
The main experiment under test was the
running
of a crank-shaft balance factor
of 35 degrees rather than the 46 degrees commonly employed
since Paul Richerdson's book apparently led us up a fools
path
some 50 years ago ! I met Paul in
53
at the Works and dearly liked him -- but he simply got his
figures wrong ! Phil Irving clearly stated the correct
balance
figure in two of his books as being 35, not 46.
Marty Dickerson long ago got the real skinny on this from
the
Master himself . In a real fury of anger Phil revealed that Paul
had blundered and got it wrong. At speeds up to 60
the
bars feel as if they are not bolted to the bike at all - but
rather
lying on your kitchen table! From 60 up
to
90 there are NO vibration periods, only a mild feeling of being
part
of the motorcycle, this gently increasing as speed mounts. We were
careful
to blue-print / equalize all recriprocating component
weights
and the flywheel run-out was held to about 1/2 thou. total,
and pinned to prevent shifting .
Sid Biberman 8/06/00
I have had some experience with
the kickstarter
problems myself, as well as having researched the malady as I too
nearly
fractured a knee shortly after buying my bike. Yes, the G48
spring
should be doubled, another spring simply wound into the first one..You
will gain a more positive engagement with two springs, and they have
been
known to slip, thereby causing the kickstarter to slam the rider's leg
into the ground.
The sticking is yet another problem, and
happens
at the top of the kickstarter's travel.. The quadrant starts to engage
with the ratchet gear and actually winds up "on end of a tooth" and
will
not go past the end of the tooth to allow the quadrant to engage the
ratchet
gear fully. It has been said to "file or eliminate the first gear on
the
quadrant" to allow it to move freely into the ratchet gear, but my
experience
has shown me that this is really not a great fix.I did not successfully
file and remove the proper amounht of material to insure me of no
sticking
at all times.
Rather, I simply do not allow the kickstarter
to go fully back to the top position. I "set" the kickstarter at about
one tooth below the top of the quadrant...it is a pretty simple
operation
actually. If you happen to allow the kickstarter to go back to the top,
rather than approximately one tooth down, simply pull in the clutch
lever,
move the kickstarter down just a touch, and you will make sure you are
engaged into the quadrant. In other words, don't kick the bike with the
kickstarter absolutely at the top of the kickstarter's travel.
I have had the kickstarter and ratchet gears
working
so sweetly that it was possible to allow the kickstarter to go all the
way to the top, however, when it might stick that once in 50 times is
enough
to frustrate you, so I just "go one tooth down" and I never have
sticking
problems.
As noted when discussing this problem
previously,
having the kickstarter slip can very easily mean a fractured knee. This
is a real serious mechanical consideration on your Vincent, so if you
have
not renewed the G 48 spring in mention in many years, it is (in
my
estimation) a MUST to do so, and please add that second
spring.
Carl Hungness 7/19/00
One way to extend the life of the
exhaust
lifter mechanism is to obtain a kill
button
type magneto points cover, and a Miller grounding type horn
button.
Use of a kill button to stop one's motor will greatly extend the life
of
the exhaust lifter mechanism. Also, according to Sid it is
important
to dial in enough slack and he recommends that the lever only begin to
engage after you have pulled it in half way. Matthew
Biberman
7/18/00
Valve Lifter Mechanism:
I do not subscribe to the notion that kicking the bike without the
compression
release will strip the splines to your kickstarter..as noted, I have
kicked
my bike for about nine years now with no spline wear noticeable. (While
speaking of spline wear, it is a GREAT idea to drill the kickstart
spline
and tap so you can run a bolt and washer up to the kickstarter
itself..I
used to have trouble with the kickstarter working its way off the
spline
until I performed this simple modification).
If I were your neighbor I'd
take off the timing cover first thing...actually just removing the
cover
won't do much good. You also have to remove the steady plate and all of
the attendant gears that go along with it. If
you
have not performed this operation previously (and lined up all the
timing
marks) be cautioned the Vincent has a "hunting tooth" and you may well
turn the engine over several dozen times before everything lines up. If
you need further instruction on how to perform the operation, I'm sure
there are many who will assist you (myself included).
Adjusting the mechanism is
no easy task either. I believe you are supposed to have about 0.015
clearance
between the roller and the lifter, but getting in to measure it is a
task
for the journeyman. I managed to adjust mine with approximately 3/8"
slack
before the mechanism started to move, and I had plenty of cable left,
and
I was able to see the mechanism working perfectly, so I put it back
together
and she now works a treat.
As far as having the
mechanism
leak, you will find numerous cures in the "40 Years On" book and I just
completed one that utilizes a valve seal out of a Triumph. I had to
make
a new outer tube, but the effort was REALLY worth the trouble..so if
you
do tear the thing apart, NOW is the time to cure the leak..and it will
leak..and you will have an oily rear wheel.
John Healy from Coventry led
me through the valve seal fix as did Rip Tragle as well..I had it
explained
to me twice to make sure I knew what I was doing. You are playing with
one of the real Vincent bugaboos here, in my estimation, and it is one
to be considered very seriously for I know what the knee damage can be.
At the same time I would
almost
Demand that your friend replace the G48 spring with TWO G48 springs,
interwound
within one another. If he is on an old bike, the G 48 is probably worn
badly and the result will be a slipped kickstarter which can (easily)
result
in a fractured knee..fractured as in bloody. I thought I had discovered
a real fix by putting in two G 48's until I discoverd that some of the
journeyman mechanics such as Dick Busby have been doing so for years.
It
will take only minutes to replace the springs. If he has never
experienced
a slipped kickstarter he is in for the most rude awakening of his life.
My best, Carl Hungness 7/18/00
Valve Lifter Mechanism:What
Carl means is that the roller on the lifter has worn into the face of
the
follower, what has happened here is that the set up was incorrectly
carried
out , such that the roller was in permanent contact with the face or
the
follower. This is deduced by Carls statement that it wore in a few
miles.
The roller should never be in contact with the follower with the engine
running !!
It is preferable to replace the roller with a
hard face , e.g. Stellite it. nothing to drop off then. When
setting
up the lifters use a bush on the camshaft the same diameter as the base
circle of the cam, so that you have an uninterrupted view of what
you are doing. Take the pushrods out , and make
sure the follower is sitting on the bush. Then sit and adjust. When you
think you have it right , put the pushrods in place adjust the tappets
and try again.
Trevor 7/18/00
Engine Balance Factor:I
was talking to a rider recently who had discovered during a rebuild
that
his Shadow is balanced to a factor of 35%. My understanding is
that
during production the line was generally balanced at a considerably
higher
factor, about 46%. I must say that riding his Shadow proved the
lower
number to be quite smooth. I investigated by doing some homework
with "Motorcycle Engineering" by the late, great Phil Irving. In
it, discussing balance and torque reactions, he states that 35% is a
very
good factor for "medium" V twins, those falling between 45 and 90
degrees.
By the way, this 35% is based on TOTAL reciprocating weight, i.e. (as I
interpret it, please correct me if I'm wrong), both piston assemblies
and
the weight of both small ends. My question is what the
general
consensus has been amongst those of you who have investigated your
machine's
balance. What numbers have you found as "stock" and what numbers
have you run with what results.
Glenn Bewley 6/29/00
Glenn, I asked PEI about the 35%
balance factor and HE said it may have
a typo. Marty Dickerson built numerous Vinnys @ 35% and, like you said,
they were smooth. Another one of those things that makes you say:
Hmmm.
Cheers, John Ulver
Cylinder Liners: .L.A.
Sleeves offer well proven and well made liners in oversize dimensions
we
have used with full success for many years . Coventry Spares
generally
carry fine quality liners in + .040" and +.060" at
reasonable
prices.
After removal and deep cleaning, the pair
of
finned cylinders are closely examined and measured / compared.
The
purpose
being to Blue-print them to identical thickness
top to bottom as well as being bored perfectly central and
perpendicular
to parallel top and bottom surfaces. Their inner bores are
taken out enough to fully clean-up and provide a smooth dead
straight
and round surface. Unwise to bore any larger than necessary as it loses
cylinder strength / rigidty .
The new liner is mounted on expanding mandrels
and its outside diameter is reduced dead true to its center and fully
larger
by .004" than the i.d. of that muff selected to mate with
it
. At the exact distance from its top where this liner
shall emerge from the bottom of that muff, this sleeve is taken
down
to suit one or the other main case register mouth bores - to a fine
finish
and a snug slide-in fit into the bolted together cases and marked
to identify this mating for correct assembly . The
remaining
liner and muff are likewise prepared and mated .
The cool liners are fully entered into the
heated
alloy muffs and held hard-in until cooled off . The top recess
and
head spigot
already having been reformed to original
dimensions
. Later, after final double grit lapping, we like to see an air gap of
.003" between the two broad faces, this representing the differance in
grain size . This will close up and come solid upon application
of
the correct torque loading figure, ie. 30 to 32 ft.lbs.
maximum
. No more is needed and actually harmful .
Before final bore and hone procedure, the
thrust
face oil delivery holes are sited carefully. These break through
below the oil-ring grooves - at BDC - not into them.
Finally, we prefer to fit a lower liner mouth girdle clamp to
prevent
any bell -mouthing while boring and honing . Good
luck
. Sid Biberman 5/22/00
Camshafts: When
Bob Guptil was playing go fast I bought Him a set of Emmericks' cams as
He was tight for $. So in 1977 the two of us head to Bonneville.
Now, Ron Kemp had built this VERY sweet engine for Bob, but neither
Parti
or the rest
of us couldn't make Bob stay out of it, and
little
by little it would go slower and slower. Anyhow, in '77 it ran 137mph
with
Mk.2's and on the next run with the Emmerick/Andrews' cams it ran
136mph.
Virtually the same, Bob pulls the cams out, hands them to me and says
something
like "You paid for them, they're no better than stock, they're Yours"!
No, I didn't hurt him. I needed the ride back home.
I took the cams and tried them out, took them
out ploted them on a spare engine wrote it down somewhere, and they are
still on the shelf. They ran OK, but the bike sounded like a Maytag
washing
machine to me. A couple of years later Harvey Crane invited me into his
Motor home at the SaltFlats to sell me some of his cams. "These got
dips
in them" says I. "Yeah, 'that's so the valve will slam shut" says
H.C.. I walked over to Dave Matson retold him the story and it turns
out
Dave had given Crane some cams to regrind correctly because they had
dips
in them and Dave wanted to Get them fixed!
A few years later in Wendover one night, we're
sitting around telling each other how smart we are when on of us who
owned
a well known cam shop let it out that he and the guy he'd bought the
business
from had ground cams for years with the Masters set up backwards!
Moral, stick with Gary Robinson, or Phil
Irving.
Cheers,
John
Vincent Rods in
order of Total weight----Big end weight-----small
end weight.
Vincent 1 607 grams-- 314---160
Vincent 2 594-------------333----208
Vincent 3 617--------------316----196
Early Carrillo
(A)
462-----240-----146
Late Carrillo
(B)
569-----314----182.
Weight of big end bush 93
gram
small end bush 30 gram.
The Vincent rods were weighed complete with
both
bushes.
The Carrillo without big end bush and small
end bush (A)
The Carrillo without big end bush but with
bronzed in small end (B)
So you can see that the Carrillo`s are not
heavier
than a standard Vincent, in either variety...and that Vincent rods have
nothing in common. Another little thing in my book suggesting
that
there is no such thing as a standard Vincent.....
Trevor Southwell 4/04/00
Regarding the extra
oil pump for the timing case
, I use a
similar Honda 50ss pump but which is not driven by an added gear and
the
intallation is more compact than the Herve Hamon system as described in
Forty years on.
I fit the pump centralised on the large idler
(for twin engine)---on the little idler rear for Comet. In place of the
std idler shaft holder I made a ??special ET66 with two ball
bearings
side to side. A slotted spindle is tight fitted into the timing
large
gear which can drive the little oil pump placed on an enlarged
steady
plate. Of course another ball bearing is needed
at the other end of the'drive shaft' at the back
of the steady plate to have a correct alignment of this idler
gear+shaft
assembly.
The oil is pumped at the bottom of the crankase
into the recess with a copper tube and an anti return ball valve at the
bottom end. The pump push the oil under pressure into the timing cover
through a n added rubber seal inserted in front of the higher steady
plate
stud after machined (an sometimes add some material)a slot and a three
mm hole in the timing cover...+special
drilled stud ,banjos,etc...
WHY THAT???Who has never heard of worn out
cams+followers+bushes+spindles
after too short mileage?? Cams+folls are lubricated by the return oil
from
the heads.....OK Cam spindle+bush via the 170 jet to convert the large
oil flow from the
original pump to ......Pressure able? to
lubricate
the camshaft plain bearings. This converted pressure is:00004
bar!..something
like that! With this added pump the cam bushes and shaft+cam followers
and cam friction are lubricated as they should be..under pressure.
Several
Twins and Comet in France are such assembled and all is all right
on this side now. After some checks at differents mileages no signs of
wear compared with the std at the same mileage.......Another
report
in 50 000more
miles!
Francois Grosset
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