C: Clutch Refreshing Vincent Twin Clutch seals and pieces

Peter Holmes

Well Known and Active Forum User
VOC Member
I can answer that question in part, Norman certainly did make a similar conversion for the Burman outer clutch plate, it does involve boring out the centre and replacing with the needle roller thrust race conversion, but you would have to check whether this is still available.
 

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
I can answer that question in part, Norman certainly did make a similar conversion for the Burman outer clutch plate, it does involve boring out the centre and replacing with the needle roller thrust race conversion, but you would have to check whether this is still available.
I an hoping to avoid boring the centre if possible so at a latter date I could revert back to the original setup.
 

timetraveller

Well Known and Active Forum User
VOC Member
Sorry coming late to this. Peter is quite right. When I was developing the kit for twins a local member and one other asked If I could make one for a Comet. I had enough pieces made for about ten bikes but only ever sold a couple from memory. By chance I came across a box with the parts in last week while looking for something else. I will go and look them out again to refresh my memory of what was done and see if I could come up with a system that does not require boring something. With the twins I managed to design it so that nothing original was modified and I would have tried to do the same with the singles. I will see what I can find and if necessary ask the local member if I can look at his to remember what was done.
 

timetraveller

Well Known and Active Forum User
VOC Member
Ok Chaps, I have now looked out the bits and pieces and this has dislodged some of the long buried memories. I can see now what I did and why. Firstly. I have two of the ali outer pressure plates and the bad news is that one has a central hole of about 14.11 mm (possibly 5/8" originally) and the other has a larger central hole, 19.95 mm (over 3/4"). Therefore, as I do not have lots of Comet parts around someone needs to tell me what they need. The conversion is relatively straight forwards and I have plenty of parts left over. The original central steel part is pressed out. I now remember that some of these had a hole worn over half way through where the push rod had been doing its best to get to freedom. This central steel part is replaced with a new design of steel insert which has a hollowed out inner face to take the needle roller thrust race and a central hole to take a locator spigot in the face of the other half of the thrust system to apply pressure to the needle roller thrust race. If anyone has a pressure plate with the smaller diameter central hole then I have checked that there is enough metal round the larger outer pieces to allow them to be machined smaller to fit into the smaller holed. Thus on the basis of these two plates there should be no need to do any boring.
With the kits for the twins I provide a new piece of silver steel, hardened at one end (the inner) and with the outer end to be cut to length to fit into the inner part of the new thrust parts. After all this time I do not remember whether the original Burman push rods are in two parts or are long enough to interface with the new parts. With the twins they are not long enough and the piece of silver steel I supply is about 7.5" long to allow the owner to cut it to length and to replace the original outer part of the pushrod.
After all this time I cannot remember what I paid for these parts but would suggest that a price of £40 per kit would be about right for a kit to include the two new steel pieces, the needle roller thrust race and a piece of silver steel if that is required. Plus P&P of course. Over to you.
 

Bill Thomas

Well Known and Active Forum User
VOC Member
In forty years on , one will find a simple tool that every twin owner should have in his tool kit. It is simple to make , and will fit in the tool tray. I t enables the clutch to be held so that the C20 nut can be fully tightened up without having to jam any thing, and risk causing any damage.
details can be found on page220 of forty years on article 58 or M.P.H. number 470
stumpy lord
Thanks Norman, Can't think why I have never seen this after all these years.
Never liked sticking wood in the wheel.
Not so bad with my 5 spoke alloy wheels !!.
Tried it last week, With an old inner plate with 2 holes and a Car tool to hold it.
Now welded a holding flat bar with a 3/8th offset, To miss the drum.
Cheers Bill.
DSCN0231 (2).JPG
 

Alyson

Well Known and Active Forum User
VOC Member
So this new seal C18/3 with aluminum spacer to slip on G3 and the oring to go to the outside of the new C18/3 spacer would appear as my out of scale rough drawing?

The theory being that oil would not leak down the C20 threads?
maybe thread sealant?
Looks like a good design. Anyone successfully using C18/3?
This C18/3 seal also allows me to ignore the C3 mod, which I think is a good design as well.


View attachment 25326
one could always use a bit of teflon tape on the threads of C20 in order to prevent the passage of oil. Alyson
 
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