yamanx Posted July 3, 2018 Report Share Posted July 3, 2018 I've just put the clutch back together after fitting new main seals, etc. When setting the tension on the clutch springs, how far do I tighten the nuts? I have assumed the tops of the pins and nuts are level, but is this about right? Quote Link to comment Share on other sites More sharing options...
twinnshock Posted July 3, 2018 Report Share Posted July 3, 2018 Can I quote myself from May 2005! Before reading quote, please be aware there is probabably as many different oppionions on this as Bultaco owners. If you want oppionions on correct oil to use, search the Bultaco forum then make you own mind up. As for modern plates probabably the best way to go as they grip better and let you get away with less spring pressure and therfore less lever effort. I have never tried it so not in a good position to advise. Quote 26th May 2005 I always run my clutches with one plate less than fitted originally (the last plate, the one just under the outer spring plate. Not sure if this makes a big difference but I tried it years ago and it seemed to improve things and have never fitted this last plate to a clutch since. All the previous advice about cable condition and arm operating levers is the place to start as if these are not in good condition or set up correctly you are wasting your time. Also new springs are a good idea with these matched for length as best as possible. I adjust the nuts so that the thread is protruding just beyond the nut and then pull in the clutch lever and hold in this position with a cable tie on the lever and handlebar. With the clutch held pulled in I then rotate the clutch via the kickstart and carfully adjust each spring adjuster until clutch plate wobble is either totally eliminated or at least reduced to the absolute minimum possible. The nuts should have about 1 to 1.5mm thread protruding. Don't forget to secure the nuts with some locking wire. Finally I replace the primary case cover and fill with 300cc of ATQF. This is what I used back in the 70's when the bikes were new. You can not teach an old dog new tricks! The older bikes do not have adjuster nuts but use a non adjustable pin and cup arrangement. My Model 80 (1971) with new springs and the one plate removed will slip the clutch with a sharp kick from the kickstater when cold but a smooth follow through kick will get her going and she never gives a problem when warmed up or actually slipping when riding. Twinnshock 1 1 Quote Link to comment Share on other sites More sharing options...
feetupfun Posted July 4, 2018 Report Share Posted July 4, 2018 If your clutch spring posts are adjustable, set the spring preload so that the kickstart will just transmit enough torque to kick the motor over cold. Also set the individual spring preloads so that the pressure plate remains parallel with the plates as it moves in and out. There are so many variables with clutch hub design and plate thickness and number of plates and spring length and spring stiffness and nut thickness and post length on Bultacos that there is no logic in recommending anything for someone else's bike regarding where the nuts should sit relative to the posts. Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted July 4, 2018 Report Share Posted July 4, 2018 there is a way to set it up with fibre plates which give more friction but less pressure. Back in the day we set them up so it would maybe just slip in top then backed it in a little bit and it was minimum preload which gives easiest pull on lever. As above new cable and tangent the arm. I prefer the long arm but you must make sure you get free play and full disengagement. cable oil pj1 every ride. Quote Link to comment Share on other sites More sharing options...
section swept Posted July 4, 2018 Report Share Posted July 4, 2018 16 hours ago, twinnshock said: Can I quote myself from May 2005! Before reading quote, please be aware there is probabably as many different oppionions on this as Bultaco owners. If you want oppionions on correct oil to use, search the Bultaco forum then make you own mind up. As for modern plates probabably the best way to go as they grip better and let you get away with less spring pressure and therfore less lever effort. I have never tried it so not in a good position to advise. Quote 26th May 2005 I always run my clutches with one plate less than fitted originally (the last plate, the one just under the outer spring plate. Not sure if this makes a big difference but I tried it years ago and it seemed to improve things and have never fitted this last plate to a clutch since. All the previous advice about cable condition and arm operating levers is the place to start as if these are not in good condition or set up correctly you are wasting your time. Also new springs are a good idea with these matched for length as best as possible. I adjust the nuts so that the thread is protruding just beyond the nut and then pull in the clutch lever and hold in this position with a cable tie on the lever and handlebar. With the clutch held pulled in I then rotate the clutch via the kickstart and carfully adjust each spring adjuster until clutch plate wobble is either totally eliminated or at least reduced to the absolute minimum possible. The nuts should have about 1 to 1.5mm thread protruding. Don't forget to secure the nuts with some locking wire. Finally I replace the primary case cover and fill with 300cc of ATQF. This is what I used back in the 70's when the bikes were new. You can not teach an old dog new tricks! The older bikes do not have adjuster nuts but use a non adjustable pin and cup arrangement. My Model 80 (1971) with new springs and the one plate removed will slip the clutch with a sharp kick from the kickstater when cold but a smooth follow through kick will get her going and she never gives a problem when warmed up or actually slipping when riding. Twinnshock Excellent?? Quote Link to comment Share on other sites More sharing options...
carl ekblom Posted July 4, 2018 Report Share Posted July 4, 2018 To get correct setting I use steel lock nuts (not nylock). Locking wire is not needed. Much easier. 1 Quote Link to comment Share on other sites More sharing options...
bullylover Posted July 5, 2018 Report Share Posted July 5, 2018 If you look in any manual including the owners manuals they all say to back the clutch nuts off 4 turns. So start from there and adjust according to slippage or clutch lever stiffness. A Venhil cable also make a big difference. 2 Quote Link to comment Share on other sites More sharing options...
Colby Posted December 7, 2020 Report Share Posted December 7, 2020 (edited) Need help with a 1972 250 Alpina & its clutch adjustment. Just had the motor rebuilt, so I don’t know how many plates are in there with out pulling the case, I’m guessing 6, that is what the manual list. This clutch drags. I have tried adjusting it with the screw & locking nut the one on the clutch itself, but nothing makes much difference. It is always engaged. The manual says to bottom the screw, then back off 1/4 turn. It gets close to disengaging, but still drags enough that I cant pull in the lever & come to a stop. This is driving me nuts & I have to get it right, the rebuild turned out beautiful except for this problem. Please help. Edited December 7, 2020 by Colby Quote Link to comment Share on other sites More sharing options...
b40rt Posted December 7, 2020 Report Share Posted December 7, 2020 What oil and quantity ? Quote Link to comment Share on other sites More sharing options...
feetupfun Posted December 7, 2020 Report Share Posted December 7, 2020 2 hours ago, Colby said: Need help with a 1972 250 Alpina & its clutch adjustment. Just had the motor rebuilt, so I don’t know how many plates are in there with out pulling the case, I’m guessing 6, that is what the manual list. This clutch drags. I have tried adjusting it with the screw & locking nut the one on the clutch itself, but nothing makes much difference. It is always engaged. The manual says to bottom the screw, then back off 1/4 turn. It gets close to disengaging, but still drags enough that I cant pull in the lever & come to a stop. This is driving me nuts & I have to get it right, the rebuild turned out beautiful except for this problem. Please help. Could be due to a few things and finding out what it is will probably require taking the cover off 2 Quote Link to comment Share on other sites More sharing options...
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