83 clutch slipping , even after full bleed, a fluid replace

[maindog]

I have been experiencing a weird problem with my 1st gen, and I need some input from the pros . did a full cleaning , flush and rebuild of the system. the clutch is fine , after about 200 miles the clutch pressure builds in the system causing no release (high lever) and clutch slippage, I break open the bleeder and let a little out and I'm back down the road with no slippage. I have rechecked , reblead, and have no leaks. all stock levers and MC. no air in the system. any Ideas guys ?. to me it seams like a venting problem ? any one else ever have this ?

[Squidley]

Unless you have something together wrong in the clutch pack, you still have an air issue. Clutches are a pain to do as you think you have all the air out, but might not. Curious to know, did you use a brake bleeder like a mighty vac to change out the fluid? There is also the possibility that the master cylinder could need rebuilding. If you haven't used a vac bleed system you might want to give that a shot.

[Yammer Dan]

Make sure hole in bottom of cylinder on handlebars is good and clean.

[Condor]

I have been experiencing a weird problem with my 1st gen, and I need some input from the pros . did a full cleaning , flush and rebuild of the system. the clutch is fine , after about 200 miles the clutch pressure builds in the system causing no release (high lever) and clutch slippage, I break open the bleeder and let a little out and I'm back down the road with no slippage. I have rechecked , reblead, and have no leaks. all stock levers and MC. no air in the system. any Ideas guys ?. to me it seams like a venting problem ? any one else ever have this ?

 

Had the same problem with my '83 when I bought her. Since it starts slipping after the motor gets up to op-temp your expansion relief hole is plugged in the reserve, or you have too much fluid in the reserve which should be kept at half the sight glass.. Looking down into the reserve you'll see two holes. One actually looks like they started to drill and then quit. At the bottm of the 'quit' hole is a very tiny pin hole. This allows hot expanded fluid to excape back into the reserve. You have a small piece of junk plugging the hole. Clean it out with a small piece of wire.... grocery store wire tie... and the system will work again. Crystals will form in old fluid and one of those crystals will get lodged in the hole. Easy to miss when rebuilding the master. So even though you've bled the heck out of everything it's stuck. Air will blow it out of there when rebuilding, but it can also be dislodged with the wire, and eventually sink down into the slave, and probably get washed out the next time you bleed the clutch.

[KarlS]

Had same problem until another member told be not to fill reservoir all the way to top. Bleed fluid out to little over half full and took care of 80% slipping. Then installed heavy duty clutch springs and was good to go.