I am not in this for commercial purposes but if the SC are out of stock of the needle roller conversion then I could supply direct. They have not re-ordered from me so perhaps they no longer sell enough to keep them in stock. If you want to do this job correctly then in addition to all the above advice fit one of the needle roller thrust races and modify the inner edge of the tube at the inner end of the C3 shoe carrier. I have mentioned this enough times on here but it is simple to do with hand tools. Cut, grind or otherwise cut a recess, it can be tapered or 'L' shaped on the inner edge of the internally splined tube. Then fit an 'o' ring into that space so that it is trapped when the C20 nut is tightened. This completely stops any oil getting into the clutch along the gearbox main shaft. No need for smearing jointing compound on the splines or other abominations. After getting this right you will find that the clutch gets dusty inside, not oily.
C: Clutch Multi-Plate Clutches
- Thread starter eharris
- Start date
Yes, Might be worth sending a P.M. to T.T. top right hand corner of this page ,
Looks like a letter !. Cheers Bill.
The seal between the bushes in the big chain wheel can give a bad oil leak into the clutch linings .
if tou would like one of normans clutch lift mods ,why not ask norman if HE has one in stock.
annother norman
Finally the penny drops. The TT is you, not a reference to the races on the IoM!
So would you like one? No pressure if you want to wait.
Not quite yet, thanks. I probably will if I feel I can get the standard clutch to work for me.
The mod to C3 you mention. The extra o-ring goes between C3 and the C18/1 seal?
Stu Spalding recommends that you use raised csk Allen screws as they use the next size Allen key up. I have never managed to source these so use flat faced csk Allen screws which need a key with flats so small that I can't see them. I also use three long screws with nuts to pull the ring down square before I insert and tighten the six spring screws. I had a box spanner with a handle fitted that was Ideal for this but I now appear to have put it somewhere safe. The long screws are often sold for fitting trailer board sockets to tow bars.
I wrestled with the standard clutch for a couple of decades including having it professionally rebuilt once. After trying different seals to keep the oil out of it, it became clear that none would last for long. During a recent complete engine overhaul, I went with the wet or dry Ducati plate clutch. It works wonderfully.
Another cause that acts similarly to clutch slip is the shearing of the G18 key which locates pinion G6 on the G3 shaft. It happened to me.
Russ Williams
USA
edited for clarity
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NO. If I have this right the C18/1 seal is the part that goes at the outer end of the gearbox main shaft. That is, it is intended to stop oil getting out of the splines. My 'o' ring mod is intended to go partly inside and at the inboard end of the shoe carrier splined shaft. That is about 3" further in than the seal you are referring to. One is trying to stop oil ever entering the splines, not getting out at the clutch end. The 'o' ring is not super critical. From memory the shaft is 1" diameter and one could use a one inch internal 1/8" section 'o' ring or a 25 mm ID by 3 mm section 'o' ring. One only needs about a five thou nip to make an 'o' ring oil tight so none of it is super accurate. To give you some idea the first time I did this, over sixty years ago, I used a conical grind stone as is used to clean up valve seats. Someone with more skill and better machinery could make a nice 'L' shaped cut out on the inside of the splined tube. I have never found a down side to this modification.
The fact that you have only now realised that the outer clutch plate is not lifting squarely suggests to me that you would benefit from someone near to you with more experience of the Vincent clutch giving you a bit of moral support. It is certainly different but not too hard to understand. Fitting a multi plate clutch without attention to detail like that will just waste your money. Learn to take time and be pernickety.
The fact that you have only now realised that the outer clutch plate is not lifting squarely suggests to me that you would benefit from someone near to you with more experience of the Vincent clutch giving you a bit of moral support. It is certainly different but not too hard to understand. Fitting a multi plate clutch without attention to detail like that will just waste your money. Learn to take time and be pernickety.