BMW R1200RT/R1250RT Forum

I have spent sometime nosing around the forum in search of an answer to my problem but to no avail. My bike recently failed its MoT for "Brake excessively binding Front [1.2.1(f)]" and it was demonstrated to me with two pumps of the front brake lever and the front wheel off the ground, the wheel does not spin or at least it moves but is obviously slowed by a binding brake. I set about removing the brake pads (which did have some corrosion on the backs) and cleaning the calipers and pistons in situ.
They were indeed pretty cruddy but when I re-assembled everything after a good clean up, the problem still existed, albeit to a slightly lesser extent.
I decided therefore to remove the calipers in order to inspect the pistons etc. I have been able to pop out the pistons but have only been able to remove them one at a time as a removed piston needs to be re-fitted in order to seal the caliper so that another can be pushed out using air pressure. I have now inspected all eight pistons with a lot of taking out and putting back in and bits of wood and a g-clamp and found pitting from corrosion on one and a ding on another.

I have decided to replace all the pistons and put in new pads but my problem is that I can't remove them all at the same time. I can pop one out and have the others protruding but I can't grip the remaining ones. "Split the caliper", I hear you shout, well if only I could. I have Brembo calipers which do not split; the casting is all one piece. I will add a picture and ask if anyone has any top tips as to how to grip the pistons and get them out, I'm all ears.

Thanks in advance.

Would it be possible to use a dummy piston,say a socket or similar.

I have a piece of thick rubber that is cut to just bigger than the brake pads and I use this with an old pad clamped in place one the piston is removed then use compressed air to remove the other side

Also it will be corrosion behind the seals causing the pistons to stick

All I did when replacing the pistons was hit a large screwdriver into the piston. This left a large enough hole to fit an adjustable pliers. Just wiggle them out. Think there are only cheap plastics. Don't hit the sides of the alloy casing
OK, it's a bodge, but it worked for me

Sorted!!!

A combination of stuffing nitrile gloves in vacant holes together with one of the old brake pads wrapped in another glove and g-clamped in, I managed to get them all out.

God loves a bodger