CL014 CLUTCH

I have a need to renew the clutch inserts that I find are of a Ferrodo type material impregnated with metal.
I have spoken to a company called SAFTEK who it appears do a reline service that entails fixing thin plates to both sides of the plates then bonding on a complete ring of friction material.  Does anyone have any experience of this Company and the method they propose and will it still be OK to run the clutch in oil ? - John Phelps 28/5/2003

I don't have experience of this firm or their technique.
However, it seems a complicated measure, and I would have thought likely to cost more than just buying the Club's friction plates. The main questions would be whether this technique could avoid any increase in the thickness of the plate, and any distortion, both of which are critical on a Velocette. Only the supplier could say whether their material will work in combination with steel plain plates and oil. - TW 28/5/2003

I had this done by Saftek at a cost of £19 incl p&p & vat. The job seemed ok and runs in oil, however I have had a thickness problem with this clutch as the chainwheel runs about 1/16 " out of line. I didn't discover this until it was put together, so I didn't measure the thickness of Saftek's linings, but they are very thin so I don't think that by itself it would cause much of a problem. - Roly Crisp 2/6/2003

I agree that doing just the chainwheel makes sense and a very useful saving if its teeth were good.
A variation in chainline of 1/16" shouldn't be too much of a problem at road speeds, in part owing to the 'tiltable' nature of the chainwheel.
The main problem from thicker friction plates would be if all three plus the chainwheel got thicker - the tongues on the outer plates could even come out of their slots. CL 007 discusses this subject, but it's a bit of a mess now and I think still has mistakes by me in it so I'll put up a revised version. It would have been interesting to know how thick your modified plate is now compared with the 0.155" that is published as the original's thickness. - TW 2/6/2003

You're right, the tongues of the outer plates were right on the edge of the chainwheel slots and there was the strong possibility of them coming out, so I bent them inwards using a vice to hold the tongues which was quite easy to do without distorting the plate. I also tweaked the inner tongues of the plate plates in the same way. I think that the Goodman's plates are altogether thicker than original.
The problem with a thicker clutch is that the felt seal easily fouls the outer chaincase so I put two gaskets behind the inner chaincase to bring the whole chaincase out, which eased the problem but created an oil leak so when I put that right in the near future I will measure all the plates and pass on the info.
I noticed that with the passing of time a lot of outer chaincases develop a distinct outward bow to them and I read in one of my books that judicial hammering with a rubber mallet can induce this effect (to get a little more freedom to the clutch), which I succesfully did, but the amount of room is limited by the secondary chain.
The run-out is nearer 1/8" which is a little more worrying do you think? - Roly Crisp 3/6/2003

There is so much slop in most people's primary chain that, if yours is typical with side-plates several thou wider than the rollers and the chain able to bend sideways by a few inches owing to wear (or some of them even when almost new!) then you'd probably get away with 1/8" run-out. 
You could get a feel for if it's tolerable by removing the shock absorber so you can freely rotate the engine sprocket by hand and watching the chain as it goes on to the front sprocket, then rotate it backwards and watch it go on to the chainwheel. The chain is not going to catch on the tip of the teeth like a push-bike derailleur, which would be disastrous, but if you can see that it is rubbing its way down the side of the teeth then wear is going to be a problem.
It's tempting to just use the 1/16" shorter sleeve gear distance-piece, B35/2 (see CL007) or grind 1/8" off your current one, but there probably isn't enough clearance between the release thrust bearing etc and the back of the clutch and it would increase the pre-load on the clutch springs unless you used shorter thrust pins. All the tolerances on the Velo clutch are pretty critical, except for lining thickness up to the point at which the tongues drop out of their slots or the outer fouls the chaincase. - TW 3/6/2003