C: Clutch Refreshing Vincent Twin Clutch seals and pieces

timetraveller

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Craig, the C20 nut does not come loose as standard. It is locked into place by the tang on the C45 spring. Originally, and possibly even now on new ones, this tang was bent through 90 degrees with rather a sharp bend. This would fatigue and break. Whenever this happened I would bend a new tang with a generously radiused corner and I have never had one break after that.

There are not multiple seals applied.. The early ones had a bonded item under the C20 and sealing compound on the gearbox mainshaft where it passes through the C3 shoe carrier tube. Later this was replaced by the C20 being modified with a recess to take the now cylindrical end of the gear box main shaft. Both ideas were intended to stop oil getting out of the splines inside the C3 and on the outside of the gearbox main shaft. My idea stops it getting in there.

Your paragraph concerning indexing of C20/C3 etc is not correct and you need to go back and either read the books/ instruction sheets or look at the parts and understand how they are intended to work.
 

Bill Thomas

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I always thought what made the nut loose was wear on the shim in the gearbox, Which I have seen almost worn to nothing, And the tang of the spring still in place. Cheers Bill.
 

stu spalding

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Neville Higgins recommended that nut C20 be fully tightened, then tightened further to line the locking slots up, never loosened. Cheers, Stu.
 

timetraveller

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Bill, I've never seen the nut loose other than when the tang on the spring failed. I am not sure how it can come loose when the nut is prevented from rotating on the main shaft by the spring tang. Confusedly yours
 

Bill Thomas

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The Shim E76 wears, We did one a few years ago, It had worn down to a thin ring, And somebody could not see it and put a new shim in there, Which took all the end float out of the input shaft.
Lucky I always give the gear box shaft a push pull, When the Clutch is off, I like to feel a bit of endfloat.
Cheers Bill.
 

greg brillus

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The shim wears because the C20 nut is not tight and the whole lot starts to move. This is also what causes most leaks, I feel it is because owners, or previous owners did not do the nut up tight enough, perhaps because they did not have the correct tools to do so. An equal amount of harm can be done by things being left loose as it can by over-tightening.............
 

stumpy lord

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Non-VOC Member
The shim wears because the C20 nut is not tight and the whole lot starts to move. This is also what causes most leaks, I feel it is because owners, or previous owners did not do the nut up tight enough, perhaps because they did not have the correct tools to do so. An equal amount of harm can be done by things being left loose as it can by over-tightening.............
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
 

craig

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VOC Member
I am not sure how much torque could be applied to the C14 clutch plate pins while tightening the C20 clutch nut using this tool.
Welding or bolting a handle to an old C21 clutch plate might be easier method of fabbing this tool.

ClutchHoldingTool.jpg
 
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