Caliper seals.

Thanks for all your advice guys..

Managed to get the piston out with, wait for it, a bicycle pump with adapter wedged into banjo bolt hole, and lots of oil and a heat gun . As you can guess, I dont have a compressor!! I'll try and send a picture, do you think its serviceable ??

What do you think

The bore should clean up fine. What's harder to discern is the condition of the piston. Clean off the grunge and look for pitting. Pitts = trash can fodder.

There are a few tiny, tiny pits . I've polished and polished it. It's as smooth as a babys bum to the touch but the pits are still there. Still trash ??

This is the worst bir. Dont suppose the piston would ever come out that far ?? I know you shouldn't save money when it comes to brakes, but, £120 for 3 piston!!

Did you have the dimensions for your front/rear Pistons?

Take measurements of your pistons, diameter, height, location and dimensions of the seal groove, then ask board members here or at a GS site to measure pistons from a similar year GS 750/850/1000.
I say this because Kawasaki, Suzuki, Yamaha and Honda often bought sub assemblies from the same vendors. Sometimes identical, and sometimes with minor changes. If these pistons are interchangeable, you can get new oem Suzuki piston and both seals as a set from Partzilla for $25.
I ran into this when I recently rebuilt the front calipers on my ZRX. They are the same calipers as used on the Hyabusa, except Suzuki specified light weight aluminum pistons instead of steel, and Suzuki sells the pistons and seals at a fraction of what Kawasaki wants. Identical dimensions, lighter weight, much cheaper. Win.

TexasKZ wrote: Take measurements of your pistons, diameter, height, location and dimensions of the seal groove, then ask board members here or at a GS site to measure pistons from a similar year GS 750/850/1000.
I say this because Kawasaki, Suzuki, Yamaha and Honda often bought sub assemblies from the same vendors. Sometimes identical, and sometimes with minor changes. If these pistons are interchangeable, you can get new oem Suzuki piston and both seals as a set from Partzilla for $25.
I ran into this when I recently rebuilt the front calipers on my ZRX. They are the same calipers as used on the Hyabusa, except Suzuki specified light weight aluminum pistons instead of steel, and Suzuki sells the pistons and seals at a fraction of what Kawasaki wants. Identical dimensions, lighter weight, much cheaper. Win.

That's good stuff to know and quite interesting. Thanks TexasKZ.
Rick H.

Yeah thanks all again. To clarify, on rebuild do I push the seal into the bore groove, then push the piston in all the way down , then fit the dust boot ? Sorry to appear dim but I wanna get it right and do it as easy as possible.
Just a side note, earlier I mentioned the mystical metal ring on the dust boot ? There isnt one on these calipers, just another groove to seat it in. Gonna be a right pain in the arse I think !!

Davey b wrote: Yeah thanks all again. To clarify, on rebuild do I push the seal into the bore groove, then push the piston in all the way down , then fit the dust boot ? Sorry to appear dim but I wanna get it right and do it as easy as possible.
Just a side note, earlier I mentioned the mystical metal ring on the dust boot ? There isnt one on these calipers, just another groove to seat it in. Gonna be a right pain in the arse I think !!

No, do as Gordone states: install the boot onto the piston, slide it down to the bottom, then install the boot lip into the mating groove in the caliper and lastly push the piston into the bore. Regarding those pitts on the pistons, I'd replace the pistons but then that's just me.

Thanks for clearing that up for me, I get it now. I've ordered 3 new pistons, good deal at £70 .. shouldn't really take chances with brakes right !!