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4punksdad
09-09-2001, 06:43 PM
My buddy shows up to ride today & informs me his rear brakes were smoked so he removed the pads. He intended to ride until the bike shop opened at noon.

He rode ok with no rear brakes until we got him a new set of pads. When I changed his pads for him, I did it the same way I do my 400EX..........no fluid loss. He had left that wheenie little tinfoil shim at home, so I installed the pads without it.

After I put it all back together, he had NO brakes. The pedal seems as if it has no pressure on it at all. We attemped to bleed the system but got all fluid, no air. He still has nothing, as if the cylinder has gone bad. Any ideas or suggestions.

09-09-2001, 09:32 PM
Just as an easy check, press down the pedal and look to see any movement in the brake line. If it moves or flexes a little, that would show that you are building pressure. Then you could look to either a frozen/blown caliper or a toasted master cylinder.

4punksdad
09-10-2001, 03:34 PM
#1) I was able to squeeze the piston back in with little problems.

#2) if the piston were frozen, I would have tons of pedal pressure & no movement?

#3) he tells me after the fact that he actually removed the parking brake housing from the caliper when he removed his brake pads.

not sure if #3 comes into play with this problem or not. I was thinking it was the master cylinder myself. The fluid level went back to normal when I squeezed the piston back into the caliper.

09-10-2001, 08:01 PM
Sounds like everything is ok with the caliper. I don't know a good way to check the mastercylinder. Maybe if the hose to the caliper could be blocked off in some way to check if the m.c. is building pressure. You might be able to remove the cap and bladder from the reservoir and see if fluid is being drawn out and returned. Maybe even be able to see fluid being return as the pedal is depressed, that would indicate fluid leaking past the seals. Keep us tuned in if you fine the cause.

kc 300EX
09-11-2001, 02:22 PM
check where the boldt attached to the actual pedal, if thats adjusted wrong, therwe will be no breaks