This weekend i got around to trying to find out why my rear brakes were dragging. upon removing the rear tire and looking at the calipers i saw the pads were un evenly worn on the left side of the rear caliper. So i tried to remove the pad release pin to get it out and to no avail it was stuck. So i checked my full service manual and saw i could remove the caliper as a whole so i did. I did so by taping the caliper gently down because their was still pressure on the rotors due to the piston being stuck.
With the caliper of i realized that not all piston were seized but only the middle larger one. the smaller end pistons pushed in normally but i cant get the middle one moved.
my question is can i just put a C clap on it and push it back in or do i need to crack a bleeder valve to get a release in hydraulic pressure. i don't want to damage any other part.
also any suggestions on removing the release pin for the pads. i have some vise grips i can try. i sprayed wd-40 on it last night in hopes that would loosen any rust.
i plan on flowing up the repair with a brake system flush. the rear disk is still in service range according to the manual and my dial calipers.
What does the fluid look like? If it's 1998 fluid in there (which would be dark brown by now), the moisture it's drawn over the years has probably caused corrosion on the bore / piston. If that's the case, I would take Bailyrock up on his offer.
first of thanks baileyrock. but it seems my calipers arent the problem. i switched out the rear caliper and bleed the whole system in hind sight minus tilting the front brake caliper. but my rear disc still stick after using the rear pedal.
one thing i noticed is my speed bleeder did keep vacuum while the bleeder valve was loose. didnt notice that on the front bleedings. this happened on the pcv and both rear caliper valves. i got clean fluid coming out of all the vavles but i dont understand why the brakes wont release. i even removed the line going into the lcv next to the bleeder valve and the opperated when i moved the rear pedal not the front handle brake lever. not sure if thats normal.
unless their is a solution im going to gut the braking system but ill be so sad cause u really want to ride. guess im paying for not bleeding when i got it from the po.
You can have fluid coming out of the bleeder valves because fluid is moving in only one direction -- it needs to flow back for that piston to release. Fluid flows from the secondary master cylinder into the PCV and then into the rear caliper's center piston. The issue is that fluid isn't flowing BACK.
Your issue has to be one of those components: caliper, PCV, secondary master cylinder. Since your caliper is fine, it's either the PCV or the secondary master cylinder.
Unbolt the metal brake line at the PCV (top of the above picture) and press on the center piston of the rear caliper. If brake fluid comes out then your PCV is fine and the issue is probably your secondary master cylinder.
You can have fluid coming out of the bleeder valves because fluid is moving in only one direction -- it needs to flow back for that piston to release. Fluid flows from the secondary master cylinder into the PCV and then into the rear caliper's center piston. The issue is that fluid isn't flowing BACK.
Your issue has to be one of those components: caliper, PCV, secondary master cylinder. Since your caliper is fine, it's either the PCV or the secondary master cylinder.
Unbolt the metal brake line at the PCV (top of the above picture) and press on the center piston of the rear caliper. If brake fluid comes out then your PCV is fine and the issue is probably your secondary master cylinder.
Good luck!
great. i knew it was a problem with one of the two. i just didnt know how to diagnose it. yeah i looked at the diagram in the repair manual and i narrowed it down.
so my next question is the pcv rebuildable or is it a replacement part.
ok so i loosened the line at the pcv so i could see if fluid was coming out when i pushed the piston. i got a fluid buildup when i pushed the center piston, so i thought the secondary master was the problem. toke the front left caliper off and noticed the secondary master was working or at least not seized though there was a lot of play in the piston from side to side. not sure thats normal.
at this point i have all three calipers of the bike and im ready to refresh them. i did notice there was a lot of sediment/rust gunky brake fluid in the bleeders ands the passages so hopefully a good clean will help the problem. maybe i broke some stuff loose because i got dirty fluid while draining the front lever for caliper removal.
planning on flushing the clutch line and radiator and oil change while shes down.
would their be a way to flush out the brake lines on the bike incase their is some sediment there as well.
End of thread · 10 posts recoveredWayback Machine snapshot 6 Nov 2014
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