Clutch plates sticking?

[badandy]

My '77 has a distinct "clunk" when starting out in first gear after the engine is warm. I have checked all possible external sources (i.e. control arm bushings, universal joints, lose motor mounts, etc) and everything checks out. I can accelerate hard and let off the throttle and no clunk. I can down shift to where it chirps the tire and no clunk. If I slip the clutch more than necessary it doesn't make the noise when starting out. I am wondering if the clutch discs are binding and then breaking lose a bit when starting out? Clutch is adjusted according to the manual. This bike sat for 16 years and I have only put just over 400 miles on it.

I know when the engine/trans is cold the clutch sometimes doesn't initially disengage completely. I have had this on other bikes and it disappears after riding a few hundred feet.

I am learning more of the anomalies of these bikes the longer I ride it. The primary drive chain slap at idle really bothers me, but I guess its something to live with.
I finally have it tuned to where it runs great at normal operating temp. It is definitely cold blooded compared to my other carbureted bikes.

[WingAdmin]

Two things can cause this:

- Engine idle speed too high
- Clutch plates not completely disengaging. Try adjusting the clutch cable. Sometimes a worn clutch can cause this, as pieces (or rivets!) cause the clutch to stay more engaged than it should.