Siezed brake piston
Author
Discussion

smifffymoto

Original Poster:

5,186 posts

231 months

Tuesday 21st November 2017
quotequote all
Only one is siezed and the bugger won't un sieze. I have tried degreaser and some unsieze stuff but to no avail,also tried tapping with a screwdriver to see if that helped free thing up but no.
Got any more ideas other than replacement brakes?

Enricogto

646 posts

171 months

Tuesday 21st November 2017
quotequote all
Empty all the oil from the brake, disconnect the caliper and soak it overnight in WD40 or similar (both inside and out).
Using a robust flat head screwdriver, try to insert it where the disc normally sits and leverage against the centre of the piston.
If it's salvageable, that should work.
Once it comes unstuck, you'll have to refurbish it polishing the piston and replacing the seals.

What brand/model is the system?

youngricharduk

238 posts

111 months

Tuesday 21st November 2017
quotequote all
I've had this issue before especially with Avid brakes. If the brakes are hydraulic try holding one piston in and pumping the brake lever then try cleaning the exposed caliper as best you can. Don't pump too much as piston might fall out, you could also open the bleed port at the brakes. If that doesn't work take the caliper off the bike and take it apart, most come in 2 pieces you can then loosen the piston by hand and re-assemble and re-bleed the brakes. I freed off my dad's brakes using this method but it can be frustrating, hope that helps.

smifffymoto

Original Poster:

5,186 posts

231 months

Tuesday 21st November 2017
quotequote all
They are Avids and I have never been that impressed with them.I have tried the tie wrap method without results.
I may just take it to the bike shop and make it their problem as I need my fork serviced but that's another tale(damn you Cannondale and your lefty needing ernie tool).