On mine '03 Sherco 290 I saw that the adjusting bolt was missing in the pedal. The bolt to adjust the stop position.

I find that the pedal was to high up when not engaged so I fitted a M5 bolt and nut, complete screwed in, and then the rear wheel just turned free and the pedal has little play.

But then after riding for about 20min I suddenly noticed that the rare brake was self engaging all the the time! The brake disc was getting hot.

After cooling down the brake came free again, how is this possible? What did I do wrong? How can I get the pedal a little lower without the adjusting bolt and nut then?

You have very slightly applied the brake so the internal vent is blocked off by the piston.

This means that when the brake fluid heats up under normal use the expansion cannot bleed back to the reservoir and hence starts to apply the brake, gets hotter and gets worse.

You need to slightly slacken the adjustment on the push rod at the cylinder. You should be able to feel a little clearance on the pedal before it starts to work the cylinder.

Edited July 20, 200917 yr by Autostream

I am assuming that this bike has been purchased used. Is it possible that the previous owner removed the positioning bolt on purpose and then adjusted the push rod that enters the master cylinder so that the brake functions properly? If that is the case when you put the positioning bolt back in you have in effect pushed the engagement rod farther into the master cylinder causing the brake to be applied.

After you get the pedal in the position that you prefer for your foot, try adjusting the engagement rod that goes into the master cylinder to see if that will fix the problem.

Just a thought.

Edited July 20, 200917 yr by ZIPPY

OK, thanks guys, I have a look at that.

I had no idea brake oil can heat up that fast.

My sherco is indeed a second hand bought.

Good luck Hope you get it sorted,

My 2000 2.9 is was bought second hand, sometimes the worst part is getting the bike set up for the way you ride it.