Stuck brake piston


Coast to Coast
Any ideas on how to get this piston out? This off of a 74 Yamaha tx500 front disc brake. I have two sets of these and both are stuck on the same side. I used my air compressor and blew air in it and got the one on the other side off but no go with these. Ideas? Just sucks because I got a second caliper in hopes it wouldn't be stuck as well.


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Been Around the Block
If the piston is sticking out a bit, you can push it back in with a g-clamp to free the seized parts. Then do what this guy ^ said and pump it out with the master cylinder. If the piston can't be pushed in any more, just try pumping it out anyway.

Rich Ard

doin' the backstroke in an estrogen ocean
Screw a grease gun into the caliper and squeeze it until the piston comes out.


You can always get it running with time or money.
Rich Ard said:
Screw a grease gun into the caliper and squeeze it until the piston comes out.

Sometimes if you are lucky the grease gun's tip will snap onto the bleed screw, and then you just need to block off the brake line hole. Well, and loosen the bleed screw a few turns :)


Active Member
Bolt them back together with one flipped around.

Hook it up to a master cylinder.

Using C-clamps, push one piston free. Then push it back in just enough for it to seal and do the other piston.


Coast to Coast
Awesome guys! Thanks. Will hook it up to the old master cylinder first and see if that works.


Strength is measured in tolerance, not mass
I boiled mine in a pan of water for a few minutes, the alloy caliper expands quicker than the steel piston, i then used a pair of vice grips and a squirt of WD40 to twist it out.


speedfourjoe ~

Who are you and when were you in my garage looking over my shoulder when I was working on stuck cast iron calipers ?



: anecdotal ~
So I was doing an otherwise routine brake job on a XS/TX with the cast iron caliper when I noticed a brake fluid leak coming from behind the glued on metal medallion . I carefully removed the emblem to find a short setscrew right in the middle of the caliper . On the phone to the owner and ...
"The piston was stuck so I drilled the caliper so I could get a punch in behind the piston and pound it out . I don't understand why they aren't all made that way ."


"In the age of information, ignorance is a choice
Rich Ard said:
Screw a grease gun into the caliper and squeeze it until the piston comes out.

+1^.. Done that before and it works like a charm... Hell of a grease mess to clean up but at least you won't damage a single piece of metal anywhere. Not even scratch the paint on the caliper. ;D

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