X$@#! caliper piston

After an hour and half of sweating in the garage last night I finally got the inside caliper piston out. If you have one that is really stuck here's what worked for me. Get it really hot with a torch. I used a MAP torch. Remove the bleeder valve and spray plenty of Liquid wrench in the bleeder opening. When it hits the hot metal it expands and helps to hydraulic the piston out. Hit the back side of the caliper with a brass faced hammer to jar the piston loose. Replace the bleeder and insert an airline into the brake line entry port and cover the inside port with your finger and hit it with blast of air. Stuff a rag in the caliper opening to protect your finger in case the piston decides to let go all at once. Don't give up and keep repeating, eventaully the heat and liquid wrench will work their magic.

Next time just drill into the outboard one and bastardly screw in a bolt but tight. Gives you something to pull out on with heat and penetrant. Same with the inboard bugger to yank out. You're gonna put in new stainless ones anyways so who cares much. Swearing helps a bunch.

i don't know how bad mine was since it was my first time, but the bike had been sitting since 91. I sprayed EVERYTHING with PB blaster and let it sit a few hours to penetrate, put it in a vise and hit it with a propane torch, and was able to take a pair of pliers and reach in, and spread the pliers open with both hands and wiggle it out. just have to find the right pair of pliers and watch your not scratching anything with them

For most of my calipher work I just use a rubber tipped air nozzle and blow them out. For the stubborn ones I have a bolt drilled through the center into which is tapped a grease fitting. I screw the bolt into the brake line hole and pump it full of grease, yes its a little messy to clean up but it works well. Dyno Dave Comeau once wrote that he used the grease gun trick loaded with water, I have not tried it, but would make for easy clean up afterwards.

GB

My inside pistons were as stuck as anyone's (about 10 years of no use) and I used the grease-gun-in-the-bleeder technique and it just slid right on out. It is messy but non-destructive.