Cleaned and rebuilt the master cylinder, works fine but after a few gear changes the clutch begins to slip and the lever is hard, crack the slave end and pressure is released, then problem returns. Why is the fluid not returning to the reservoir?
I'm no expert but when I remove the master cylinder cap and seal, then pump the clutch lever, you can see the fluid return as a jet through the small return hole at the bottom of the master cylinder when the lever is released. Is this happening? I have read that sometimes the return hole can be blocked causing the clutch to slip. BTW your post header talks about brake problems.
Thanks Wattie, first thats a small hole, I had to make a needle file into a fine probe to get into it but hey presto I got a squirt of fluid out of it and the CLUTCH lever returns every time. Front brake? oldtimers brain fade!!
Typical reason for this problem is when the handlebar lever is prevented from fully returning home to the ‘at rest’ position and the port remains covered by the lip of the rubber seal preventing the fluid returning to the reservoir.
