Tip for Removing Caliper Pistons the Easy Way

[Orange4]

Hi. I didn't read up about this before I did it, but my solution turned out to be super easy.

1. Ready a container with a funnel near the caliper you are working on for the used fluid you will be pouring out of the caliper. Don't forget safety and wear glasses and gloves. You don't want brake fluid on your skin or in your eyes. Don't worry about the fluid spraying. It won't happen if you follow the instructions. Can't say the same for the compressed air removal.

2.Open the reservoir. You may have to add some fluid during the procedure.

3. Unbolt the caliper from the fork or caliper arm but leave the hose attached. Remove the pads, all the hardware and the rubber boot which is held on with a steel ring.

4.Turn the caliper so the piston faces up and keep the piston level so the fluid does not spill when it comes out. Then simply pump the brake lever and watch the piston work it's way out. Keep an eye on the fluid level in the reservoir and add some if needed. Go slow when you near the end and pull the piston out the last little bit by hand. Pour the fluid into your prepared container.

5. If you are doing the front pair of calipers then the next step is to unbolt the hose from the caliper you just un-pistoned and find a nut that fits on the banjo bolt. Use the copper washers and install the nut on the banjo with the bolt to hold the pressure in when you push the piston out of the other caliper.

6. For the second caliper, Rinse and repeat... Safe, easy and clean.

Hope this helps. Sorry no pics. I only have two hands and the wife was not around when I did this.

[Winterhawk]

I've done some that were seized up so bad that I had to drill a hole in the opposite side and press the piston out on a press. LOL Then weld the hole up on the helliarc and smooth it out.

I have a TIG welder and am Aircraft Certified if anyone needs aluminum welded or Fab.

[ViperRon]

Good to know Winterhawk. Next time before drilling the hole there are 2 different possibilities. 1st is drain as much fluid as possible out put a bolt in where hose bolts on. Put cylinder assembly in a vice piston facing away. Heat it with a torch and the heat will pop the piston out. Putting a cover rag over it is a good idea to protect from splash. 2nd is to get a grease fitting to screw into bleeder hole and use a grease gun to force piston out. Grease gun definitely safer but depends on what you have and want to clean up.

[Winterhawk]

My latest one was easy. just put compressed air into the banjo bolt hole and it blew them all right out. Got lucky I guess.

[ViperRon]

Yes maybe lucky but with all things on this bike one guy has it easy and another goes threw hell on the simplest things. The trick is have a plan A,B, and C. The great thing here is people on the site can and will give you several alternatives for every possible procedure. Personally I would never have drilled it because I do not have you living next door and anyone welding aluminum parts wants a fortune to do it here. However when the one that stuck on me finally came loose in the little toaster oven in the kitchen it came out like a canon ball blasting the little oven to bits making unavoidable noise attracting my girlfriend.

[GLoweVA]

However when the one that stuck on me finally came loose in the little toaster oven in the kitchen it came out like a canon ball blasting the little oven to bits making unavoidable noise attracting my girlfriend.

WOW, that must have been a sight!

[Radioguylogs]

...attracting my girlfriend.

That's a good thing. Nothing I do attracts women anymore.

My favorite techniques were already covered above, but in the order of my favorite:

(1) Use the rear MC to push them out- dependable, not too messy, nothing broken.

(2) Grease gun- safe, usually works, but messy.

(3) Air compressor @ 90psi- Dangerous! (even with a rag over it), and frequently doesn't work for me.

[bikerphil]

Best method I have used (thanks crazy steve) is to fill the caliper with brake fluid, plug the banjo bolt hole with a bolt, and attach the grease gun hose to the open bleeder screw and pump. Less grease needed this way and 1000+ psi of hydraulic pressure.

[MPittma100]

Caliper

At some point, when a caliper has become too stubborn, it may be a good idea to call/PM Andreas to get a used one to rebuild?

MP