Hi

got a bit of a problemo.

I bought a set of Hope brakes for 80 quid front mono m4 and rear mono mini (black caliper and gold bore caps)

i have bled them but i sometimes have a problem with the rear when out riding. When i am constanly using it (like slightly holding the lever when going down a hill, that sort of thing) it heats up. with the heat, the pistons move in slightly and grip the disc, making it harrder to pedal. This carrys on until it gets reall yhard topedal and then i stop. when i lift the rear wheel up and spin it, it just stops straight away. i felt the caliper, and it was really hot.

I've bled it quite a few time, just to make sure any air in the system is out. Maybe if there is air in it, that would expand with the heat and cause it?

What can be done to resolve this problem?

Caliper rebuild?

I saw somewhere on this forum about bleeding, that there could be air behind the piston which does not get bled out?

i dunno :S


Thanks

the oil will also expand when it gets hot.

Take the wheel and pads out, squeeze the lever so that the pistons begin to move. If one moves and the other doesnt, that piston is 'lazy.' Get some cleaner (speed degreaser or disc cleaner etc) and apply to piston. This should free that piston up and hopefully sorting your problem.

As said above, check that your caliper is alligned.

Yeah a rebuild sounds like a good idea. I had my e4 rebuilt by crc a couple of years ago, worked a treat after that. not sure if they still do brake rebuilds though.

On a different note, I had bought some 2nd c2's for £60 a while ago, the previous owner proudly told me they'd just had new adjusters. They were alright just riding around, but on the first hill they heated up really badly. The numpty had put c2 (closed) master cylinder topcaps on an o2  (open) calliper! Doh! 

personaly id say it sounds like its the fluid boiling up

simple...

piston seals have gone so pistons seize up and wont go back

new piston/seal kit