Damn Brakes!!!!!

ross79 · Post by **ross79** » Fri Feb 02, 2007 7:47 am

Just changed my brake pads last night on the 12. I decided to go with the Fren S3. Installation went smoothly but now I'm getting that cicada sound. They're definately rubbing as it's hard to move the bike around.
Problem is once I got to work this morning, the REAR brake went completely!! I don't use the rear much, just around the car park, but it sank right to the bottom!

I quickly checked to see if the caliper is still on, but that all looks fine, I use locktite on everything. I've probably done a bit over 50kays on them now. Any ideas?????

Strika · Post by **Strika** » Fri Feb 02, 2007 8:27 am

Did you pump the rear brake lever back up after fitting the pads? Sounds like not!

Stace · Post by **Stace** » Fri Feb 02, 2007 8:34 am

Strika wrote:Did you pump the rear brake lever back up after fitting the pads? Sounds like not!

If unsure how to do this just check with Marty A.K.A. Strika. He has to do it with his penis, Old war injury apparently

FrogZ · Post by **FrogZ** » Fri Feb 02, 2007 8:38 am

Whats wrong with the cicada sound, most/all of them made it from new.
As to the other, more info please, but I am guessing what Strika said and you need to pump the rear, IF you didnt bleed it and refill the reservoir its a good starting point (not that you should have needed too). ALWAYS check the bloody things work before going for a ride

You can overfill them too, by having worn pads in and filling the reservoir, then installing new pads and pushing the pistons back in (if you can

). Wouldnt be noticable until it heated up but and locked the brakes ON (not off, oops, back to my corner)

ross79 · Post by **ross79** » Fri Feb 02, 2007 9:09 am

Done all that. I did the brake bleeding last week. Felt great but with only 1mm left on the pads I thought I better change the pads asap. So that's what I did last night.
Put the pads in, checked fluid levels, all fine. Pumped the brakes up before riding, all went as planned. Took the bike for a quick spin to the gym and back and it all worked fine except that you can feel the brakes dragging a little on the discs hence the cicada sound. I'm usuming once they're bed in they should stop dragging as I hardly need to use the brakes to keep the bike from rolling back when stationary on a hill.
So I retired the bike for the night. I always check my brakes before riding. They were all working till I got to work and tried the rear brake only to find it just sank to the bottom

FrogZ · Post by **FrogZ** » Fri Feb 02, 2007 9:27 am

Apply the brakes lightly to bed in (should already be done by the sound of it) any high points will be taken off, there should be NO drag. If there is they are "pumped up" and need to be released through the bleeder.
IMHO.
As for the back one, if they have "gone to the bottom" of the travel there is obv. something wrong. Check all connections and rebleed. If it still does it you obv have a leak somewhere and if it is not connectors then it is a seal, check for fluid leaks, you should be able to smell and see it.
If not it is a master or slave leak.
have fun (NOT)

ross79 · Post by **ross79** » Fri Feb 02, 2007 9:33 am

FrogZ wrote:Apply the brakes lightly to bed in (should already be done by the sound of it) any high points will be taken off, there should be NO drag. If there is they are "pumped up" and need to be released through the bleeder.
IMHO.
As for the back one, if they have "gone to the bottom" of the travel there is obv. something wrong. Check all connections and rebleed. If it still does it you obv have a leak somewhere and if it is not connectors then it is a seal, check for fluid leaks, you should be able to smell and see it.
If not it is a master or slave leak.
have fun (NOT)

Thanks frogz, will do some more bleeding tonight. Can't see or smell any fluid leaking on the rear.

FrogZ · Post by **FrogZ** » Fri Feb 02, 2007 9:36 am

If you did I would suspect Neka had come to SBK early and snuck in while you were asleep

FrogZ · Post by **FrogZ** » Fri Feb 02, 2007 9:39 am

There is a slight chance if you leave them rubbing they will glaze up too (get all shiney and not work)
If so take to them with some sandpaper.

ross79 · Post by **ross79** » Fri Feb 02, 2007 9:43 am

FrogZ wrote:There is a slight chance if you leave them rubbing they will glaze up too (get all shiney and not work)
If so take to them with some sandpaper.

Thanks for the tip. They'll probably glaze up quick as I ride 80kays each day to and from work. Will grab some sand paper on the way home tonight. What grade should I use? 100 grade?

mike-s · Post by **mike-s** » Fri Feb 02, 2007 1:05 pm

i'd say 200-250, you only need to take a fraction of a mm or so off.

oh and r.e. the sticking, even though its a reasonably new bike, the seals on the brakes could be shot. they might not leak, but they may not be letting the pistons retract enough after you use them. Another sign of this is if you get uneven wear on each pad, like one piston is pushing more than the other.

ross79 · Post by **ross79** » Fri Feb 02, 2007 1:46 pm

mike-s wrote:i'd say 200-250, you only need to take a fraction of a mm or so off.

oh and r.e. the sticking, even though its a reasonably new bike, the seals on the brakes could be shot. they might not leak, but they may not be letting the pistons retract enough after you use them. Another sign of this is if you get uneven wear on each pad, like one piston is pushing more than the other.

I'll grab some 200 on the way home. I'll check my old pads tonight to see what the wear is like, I'm pretty sure they all looked pretty even when I pulled them out.

Aussie Ninja · Post by **Aussie Ninja** » Fri Feb 02, 2007 2:22 pm

Don't know if this will help but the pistons in the tokicos can get stuck out sometimes, as in when you release the lever the pistons don't move back at all and that side ramains in contact with the disc. Happened to me. Outer pad ok, inner pad not there.

When I changed the pads hit the caliper with some cleaner, all sorted.

ross79 · Post by **ross79** » Fri Feb 02, 2007 2:39 pm

Aussie Ninja wrote:Don't know if this will help but the pistons in the tokicos can get stuck out sometimes, as in when you release the lever the pistons don't move back at all and that side ramains in contact with the disc. Happened to me. Outer pad ok, inner pad not there. When I changed the pads hit the caliper with some cleaner, all sorted.

Thanks, will add CRC to my list. Hopefully will have it sorted tonight.

photomike666 · Post by **photomike666** » Fri Feb 02, 2007 5:27 pm

ross79 wrote:
Aussie Ninja wrote:Don't know if this will help but the pistons in the tokicos can get stuck out sometimes, as in when you release the lever the pistons don't move back at all and that side ramains in contact with the disc. Happened to me. Outer pad ok, inner pad not there. When I changed the pads hit the caliper with some cleaner, all sorted.
Thanks, will add CRC to my list. Hopefully will have it sorted tonight.

I'd be more inclined to use copper grease on the piston. Is what a decent shop will use, and stays where you put it unlike CRC.

I'd say pump brake up with everything in place, remove pads and grease sides of piston. Now push piston back in, copper grease back of pad to stop squeal and refit. Everything should be OK.