Hacked off as have just had a reba fitted by LBS but sadly they didn’t have time to fix the breaks. Anyway my fault as I know it was a tad temperamental. Question is there anything I can do at home to free it up? It’s borderline unridable (wheel turns maybe one rotation before sticking)

Also when it take it in should I ask/assume seals will be replaced when its stripped down

ta

MC

had the same problem myself when I bought a bike second hand.

A few websites / forums say pump them out and spray qt85, but then some say this contaminates the DOT. I just got the pistons out, cleaned with IPA, actually replaced the rear ones with new phenolic as they are only a fiver from CRC and they were in bad nick, and rebled. Took ages becuase I was new to hydrualic discs, but they work beautifully well now…

What are phenolic – different brand of piston – sorry if this is a daft question!

Phenolic pistons are a plastic not Metal ones like you have atm. I have a spare set of phenolic pistons and caliper seals if you are interested.

May be interested – guess they are new and would be for any version of mini? (mine are 5 -6 years old)

How much were you thinking?

thanks

MC

and they’re the orginal mini’s rather than the mono mini’s look like this

http://images.google.co.uk/imgres?imgurl=http://drew81.com/file.php%3Fid%3D331%26width%3D440px%26height%3D330px&imgrefurl=http://drew81.com/332_hope_mini_rear_hydraulic_mountain_bike_brake.htm&usg=__fpetG7PW4m8JYSRifL3_ZPAAnKo=&h=330&w=440&sz=20&hl=en&start=12&um=1&tbnid=WMpBGjjzcRhROM:&tbnh=95&tbnw=127&prev=/images%3Fq%3Dhope%2Bmini%2Bbrake%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DG

thanks

Take the pads out and pump the lever a little bit gently to push the pistons out. You may find one moves more easily – hold it in and pull the lever again to get the other one to move. Clean the exposed part of the piston and lube – some folk use brake fluid – I use silicone / rubber grease. Push piston back in and refit pads – this might work if the piston is not in too bad shape. You can work the piston in and out a few times

Otherwise its a case of removing the pistons completely and cleaning them up – if you do this you might get away without new seals but I wouldn’t do it without new seals to hand as seals are cheap and there is a good chance you will damage the seals.

Don’t use GT85 or similar to lube the pistons – it might contaminate the seals and make them either swell or leak.

cheers TD but PK_XC sorted me out with some new pistons.