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Vincent Brakes - an ongoing collection of VOC members experience and recomendations that should be valuable to review.


The front brake I use is a 230 mm Grimeca modified. I made an aluminium  brake plate to replace the Grimeca plate which looks like the Vincent one (middle black, polished water excluder) and fitted in it the Grimeca components (brake shoes and cams ). The benefit of this is that I have the brake plate anchor at the right place to be inserted as the std Vincent into the fork blades. I have made the brakes levers look like the std vin' and using some H13 washers for good ajustment. I have arranged these levers in correct place to use the cable brakes std 'route' and the balance beam . The original speedo gearbox is reused  on the right side, also I have inserted a magnet into the H23  speedo gear ring  and installed inside the r/h brakeplate a pushbike electronic speedo pick up so there is just a wire to route along the blade to the little speedo clamped on the handlebar; it gives the right speed (good to check the Smith), average speed, time,  max. speed, trip distance. ect; useful gadget.

The braking is far better than any very good std or 'racing brake' Vincent  but I think it still needs to bed in because I  feel 'sponginess' at the brake lever ...especially when hot. I will ride the bike with the brake cables and the balance beam  for a few more months and will change for twin lever cables without the balance beam to see what happens!

Several riders asked me to make the same for their machines.  I need to test and improve it more before to do some copies .
This is not a cheap modification but a complete wheel assembly. Grimeca brake and hub cost about £300  + 36 holes rim + spokes + brake plates castings and machining + spindle + levers  + and +   ....I don't dare to calculate, may be £500 !
I can suply some photos if you want to make your own.   Francois Grosset  1/12/03

Replacements: I haven't tried a different drum brake but I did fit double discs to the front and low and behold it stops quickly without panic or fear. no fade, dust or adjusting every week. Discs off a Honda CB 250 dream and calipers are Grimeca twin opposed piston intended for a late model Triumph T140 I think. The disc with a little modification will fit a Vincent hub. For more info contact Dave Lawrence in Derby UK.  Roger Lord  11/16/02
I have a 9'' dia. twin drum, twin leading shoe Grimeca brake fitted to my D. Not only does it ''look the part'' it is an excellent stopper, especially two up and 100lbs of camping gear as those who travelled with me at the International can testify.  The down side is that it is 5lbs heavier than standard, although it does not seem to affect the handling, and it needs to be laced into a new rim.  Jeff Bowen  2/9/02
Spongy Brakes: Grab hold of your brake lever, gently pull back until you feel resistance. Watch the brake operating arm on the plate. Continue putting pressure on the lever, does the actuating arm move a little more or does it remain stationary?  Did the lever move more after you applied further pressure?

1.  If the handlebar lever moved more and the actuating lever remained stationary, we can say it is the combined cable mechanism squashing up.

2.  If the actuating arm continued to move after you felt resistance and the handlebar lever travelled on, you have to consider that something inside the drum  is moving.  If the shoe is hard up against the drum, what can move ?  Nothing should until the drum is rotating. Then the servo effect may cause the shoe to bite into the drum. That will not be much. Is the shoe material compressing ? Try and squash some under a press. Which leaves you with one answer which is demonstrated by my cutaway hub assembly. You can watch the shoe touch the drum at the pivot end, and then bend itself to form its curvature to fit the drum.  How much it moves depends upon the wear.  Trevor  12/15/01

My father and i have recently fitted double front disc brakes to two 'c' Rapides and I will attempt to describe the fitting and assembly. The discs are off a Honda CB250N and the central hole is about 1mm (.040 inches) smaller than the alloy hub on a Vin and are 5 bolt fixing so they can be made to fit very well with no dragged holes or holes breaking out of edges.  The calipers are Grimeca twin opposing piston units which are supplied as direct replacements for the Triumph T160 and other disc braked models and the master cylinder is off a YPVS Yamaha.

The fitting is fairy straight forward. The discs are modified to fit the Vincent hub and are bolted on with a spacer between the disc and spoke flange to enable the calipers to clear the spokes. The calipers are mounted on outrigger plates held in place by the front wheel spindle and a special bolt going through the brake torque mount on the fork legs. The speedo drive is covered by a dummy back plate on the right hand side to carry the drive adaptor.

It works extremely well and is powerful, progressive, with plenty of feel and feed back. I can E-mail or snail mail pictures if any one is interested. Please note this mod was designed and manufactured by Dave Lambert of Derby, UK who is designing a single disc rear brake along the same lines.  For road safety in modern traffic this is a must-do mod. Whether you do this one
or another one, better brakes are a worthwhile investment. It certainly beats the hell out of pulling the lever back to the bar and praying.  Roger Lord   8/5/01

Brake Rivets: Rivets of every description are available by the llb or less from Rivet Supply Co. Ltd of Power Road, Chiswick, LondonW4 on the outskirts of London (junction M4 and North Circular). Wholesalers and Manufacturers.

Phone 020 8994 0102 or 6238 or 8484 or FAX 020 8747 1345.    A truly fantastic company, but be clear in what you wish--there are a million variations of size, head style and material.  They can also supply all types of "set".                        Arthur Farrow  9/29/00

From: Arthur Farrow

The other day I posted a note saying that if anybody wanted some of Derek Sayers (non advertised) front brake cables I would be happy to act as internet go-between since Derek is not connected.Many of you seem interested. I do emphasise my only interest is as an entirely satisfied customer of Dels who lives on the front brake. So here is the info and how you can order :- 2 types SHORT and LONG. Originally SHORT was fitted going to RIGHT arm of Balance Beam.No stop.( A,B & some C?) Then changed to LONG going to LEFT arm of Balance Beam with stop.This is the more normal set-up most of us have. Cable type: very large diameter, as big as the rear cable. As original Black with red stripe running down (weird) Some years ago and partly in response to my whinge Del had a batch made which sold promptly. Others may from time to time have had a few bashed out, but Del always has them and seems to me to be the modern reviver and thus deserves our business. ! have the cables on my A, B and C. HAPPY HAPPY HAPPY, but do remember they are PART of the solution. Cost to overseas orderers is £39 all territories of the world, inc air mail/packing in a stout padded bag. Different currency to £sterling is acceptable but only in the form of notes and with a surcharge of £3 to allow for exchange costs Del has no Credit cards facility. Bulk orders by negotiation!! Sales to UK are cheaper of course. Phone him for info. Cheques in £sterling or even notes (left over from International Rally?)are of course welcomed.

Order direct:  Mr. Derek Sayer, 75A, Grosvenor Park, Camberwell, London SE5 0NJ, Great Britain.  Phone/Fax (44) 171 703 6205 (change in april to 0207 703 6205)

I received today a set of front brake cables supplied by Derek Sayer.  These were brought to our attention a while back by Arthur Farrow, but have been undergoing testing and are only just now actually available.

I'm happy to report that they are very nicely made, and much heavier-duty than the usual cables such as were on my bike.  The brake action on my Shadow is substantially less spongy than before, and braking is much more effective with the firmer feel leading to higher pressure at the brake shoes.  These cables aren't precisely cheap, but are well worth the investment in my view.

Derek is not on email, but his address is 75a  Grosvenor Park, Camberwell,
London SE5 0NJ; phone 071-703-6205.     Dave Hartner  4/18/00

Bowden Cables , the originators of the British standard cable controls seen in general use also made a far superior racing grade product called Bowdenex . Identified by red flects in its outer woven housing differed in structure from its more common offering by the peculiar form of the wire from which its outer coil was wound . Rather than being round section wire -this was FLAT in section ! Thus a sries of flat to flat against flat , this being absolutely non- compressionable unlike its cheaper round wire brother which IS NOT ! All Pukka Race bikes utilized this far more stable and dependable pattern which rarely needed adjusting during a race -there being no shortening of its outer housing . Much better for clutch and brake control use . My street Lightning used this stuff throughout , front to rear never needing a replacement for 10 years of constant use . Superb and dramatically better !   S.M. Biberman 9/00
By 1955 the performance of my modified Rapide , now in Road Lightning trim encluding ribbed drums and BL plates far out stripped its braking ability . In despiration I relined with material used on Zundapt KS- 601 s which had a heavy quantity of metal wire ( bronze ) in its mix. This facinated me and I reas- one that these very heavy machines which hauled S/cars all over Europe must need powerful and effective brakes. I fitted these segments to my Vincent shoes and was amazed at the difference ! Both wheels could be brought right up to the very edge of what is referred to as incipient slippage and held there. I ran my own tests before and after this modification was done , on the very same secluded road . ts surface was chipped concrete thus offered a perfect and consistant surface. My stopping distance went down very dramatically to 19 & 1/2 feet from 30 mph . I acheved this figure twice and extreme care and steely nerves were needed as well as an altered riding position. One MUST sit well back onto the rear portion of the seat with arms locked ridigedly outstretched and a firm grip on the bars. All of this to position more weight on the rear wheel and to maintain secure control and grip on the motorcycle lest you go over the bars. These linings wore so slowly that 5 years later they were still on those shoes when converted to a dragster . Trevor is of course correct that the leading edge Must contact initally to set- up the wedging or self servo effect or one has in effect twin FOLLOWING shoes! Thus the assembled shoes on their plate is turned to match the drum s surface after a bit of feeler gage is inserted between the cam and its shoe faces to partually expand them , this to bring that leading edge out to where it can kiss the drum surface . This important situation is all important to having an effective and fierce bite. This edge MUST be champhered as they all need be to prevent locking -up the wheel , this a real possibility ! All brass rivets of course were used but today I would only use bonding.  Sid .12 Feb 2000 

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