Re-building the caliper. I have two assembly's (original one with bike= crap, other assembly decent, but needs rebuilt) and I was trying to remove the big piston. Can NOT get it out, even gripped the very edge and am able to work it back and forth with channel locks (I did not want to, but can not grip it to move it, will have some burrs to smooth out). It is not frozen, just very stiff. I can see some of the oil seals falling out (feels like the seals are binding it).

How do I get it out?
Mike????

Thanks.

 

Place a shop rag between the piston and the outer section if the caliper and use a shot of air into the brake line hole from an air compressor and it will pop right out. It doesn't need much air pressure to pop it out so be careful and keep your fingers on the outside of the caliper otherwise you'll be sorry and in pain!

Jeff