brake piston removal

Donlon McGovern mcgovern at
Sun Nov 4 23:23:06 PST 2007

It sounds like you have accumulated water in your brake fluid, hence the 
cloudy, creamy texture. Good thing you are disassembling them. If I were 
doing it I would bleed all the old fluid out of the system with clean fluid 
and get all the creamy stuff out. Then, once you have removed the caliper 
assemblies you should be able to just squeeze the brake lever and push the 
pucks out enough to pull them out by hand. You will probably have to replace 
the rubber seals and use a fine abrasive emery paper to gently scrub the 
cylinders if they are rusty. But, if they are just cruddy, a good brake 
cleaning fluid should flush the crud out. With the seals back in place you 
should be able to push the pucks back in but you might need a stiff section 
of thin board to get them flat with the surface of the caliper assembly. 
Mount them back, squeeze the brake lever to reseat the pads and then bleed 
again until you get all the air bubbles out. There may be other suggestions 
from Zoran or Jim Stewart or any other listers that have done this far more 
often than me. I'd say you biggest problem is not bleeding your brakes often 
enough to purge water out of the system. Remember, brake fluid is 
hydroscopic, it absorbs dihydrogen oxide (fancy name for water).
----- Original Message ----- 
From: "David kerr"
 So, this is the first time I've disassembled the brakes on my '99 SV650x. 
So far I have discovered that the brake  "fluid" was white and the 
cinsistancy of room temperature sour cream. What causes this?
 I've also discovered that one or two of the seals are pushed out and 
showing next to the pistons.
2nd Question: How in the world do you remove the brake pistons without the 
use of compressed air from the back as the service manual suggests. I 
obviously don't want to scratch, scar or squeeze the pistons, so what's the 
Lastly, any tips on cleaning and replacing the same pistons?

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