V4R clutch slipping

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(Check) If there is inadequate free play in the clutch lever, when the fluid is heated by the engine the expanding fluid cannot return to the reservoir — and pushes the slave cylinder causing slippage. When the fluid cools the clutch stops slipping. Aftermarket levers that change the master cylinder rest position are the usual cause. Adjustment by clueless mechanics is the other.
 
(Check) If there is inadequate free play in the clutch lever, when the fluid is heated by the engine the expanding fluid cannot return to the reservoir — and pushes the slave cylinder causing slippage. When the fluid cools the clutch stops slipping. Aftermarket levers that change the master cylinder rest position are the usual cause. Adjustment by clueless mechanics is the other.

I've seen this reply by you in other forums and been meaning to reply. So before I get to measuring the clutch stack, I wanted to troubleshoot this. There indeed was zero free play in the clutch lever, and I've added what I feel like is 5-10% free play in by adjusting (shortening) the plunger length. However, pulling in the clutch still does not cause any air bubbles to pop up in the reservoir, which seems to indicate that the bypass valve in the master cylinder is still blocking the fluid return, is that right? If so, how do I "reset" the valve?
 
If you're sure that now you have enough lever freeplay to prevent the rest position of the primary cup seal from covering the vent port, you should see the fluid surface ripple from a squirt of fluid (not bubbles) into the reservoir during the initial part of the lever pull. If not, the small vent port is plugged.
 

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nicceee,,, something similar to this is what was responsible for my front brakes locking up during 1st test ride. it was my fault though.
 
Yeah I saw your post and thought the same thing but it seemed more involved... glad you sorted it out!
 

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