Hi everyone,
I am trying to figure out the clutch problem on a 1968 A50 that I just restored. I apologize if this has been answered before but I couldn't find anything. The clutch is fine when the engine is cold but after riding for 30 min or so the clutch becomes increasingly stiff. If I let everything cool down, the clutch goes back to being light. There is plenty of oil. The clutch pressure plate moves fine, everything was adjusted according to the service manual. I looked at the push rod. The flat end has a dimple in the middle, the cupped end fits the ball in the plunger. Everything moves freely when cold. Could the heat cause something to expand making the clutch harder to pull? Has anyone come across this? I see a lot of posts about adjusting a stiff clutch, but the clutch is fine when cold.
Cheers, Nick
I would have thought there are 2 possibilities: either the actuating mechanism is stiffening up when the engine gets hot or the clutch pressure plate springs are limiting movement.
To determine which of these 2 possibilities it is, just remove the clutch adjuster when the engine gets hot and see whether the actuating mechanism moves the rod in and out freely or not.
I think it is more likely to be due to problems with the pressure plate movement and, unfortunately, you would first need to take off the chaincase cover to check this. It may simply be due to the springs nuts have been tightened too much.
Hi Nick,
The link below is a good article regarding the A50/65 clutch, it might give some ideas:
https://sumpmagazine.com/classic-bike-workshop/bsa-a65-clutch.htm
It is also preferable to check the plate run out when adjusting the springs rather than any other method.
It would be interesting for you to describe or post an image of the cable route you have adopted. I believe as the years progressed it was changed to a "slacker" route due the problems you described.
Best wishes...