One piston jammed!

On my brembo brakes that is. In fact it's not jammed, it just moves so slow when compared to the other piston. If I clamp the good piston down, the problem piston pushes out lovely.

Should try bleeding? I'm gonna put this off until my new pads come through. This all came about btw when my fork seal blew and oil went all over the calliper. By the the end of the ride it was caked in a mud and oil. When the fork was removed for servicing I set about cleaning the calliper. I presume the pads are ruined as they were saturated in oil. annoying as they were new!

Just another annoyance I thought I would mention. When the fork seals were being sorted it was found the bottom pre load spacer was missing on one fork (the blown fork). To my knowledge the forks have never been looked at so must have left the factory incomplete!!

Bleeding will not make a difference on a multi piston caliper that has a slow piston. Must likely, debris got packed in and is causing resistence. Chances are, pulling the pads, removing the caliper from the forks (leave the brake line attached) and clean it as much as possible will fix you up.

Thanks for the reply but the calliper has been cleaned super thoroughly and the piston pumped out loads, lubed, pushed back in and repeated.

The next possibly is the seal swelled from contact with the fork oil or a cleaning solvent you've used. The cleaning solvents will often evaporate and the seal will return to normal. Some non-volitale chemicals like some specialty oils will not and the solution then is a seal replacement.

once you apply the brakes, won't the pressure just equalize anyways?

how about a rebuild? a set of seals for them cant be too much...can they?

id wager the fork oil damaged the seal on that piston. it likely wont get better from cleaning/bleeding.

Hmmm. I don't think they will equalise under light braking. so will be inconsistent in feel and wear.

I think a rebuild is in order. I will also try that reverse way of bleeding with a syringe.

Bleeding will not do anything for your problem. Piston return is purely a function of the square section piston seals.

Indeed I will try and find a service kit. Just mentioning the bleeding as it will have to be done regardless.

Do I go through Brenbo or Huskysport? Prob try Husky first but will have to wait till tuesday. Bank holiday and someone got married yesterday!

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