[BigHitWannabe]

I have Hayes Hydraulic discs on my bike. I've had a problem with them rubbing. It's not bad, but that little squeel drives me nuts. I removed the pads, and pushed the pistons in. They move pretty far when I push them. I reinstall the pads, and give the levers a few squeezes. It takes a few squeezes to firm up. When they firm up, I an look and see the pads right back against the rotor again. The pistons are not recessing back far enough. What do I do now? Other than this one problem, these brakes are awesome. Thanks

 

[pugslybell]

take your pads out, push pistons back in reinstall pads, loosen bolts that attach brake to adapters, place two to four business cards between pads and the roter(two on each side and four if you can get them in). Reef on the lever(with the bolts loose and cards in
0 tighten bolts. Squeeze lever hard ten to fifteen times, this should set the pistons and you should have no more rubbing.

 

[caputo1989]

mine do the same thing and i just deel with it

 

[TrekBro]

you have to clean the sides of the pistons they can accumulate dirt, try with a toothbrush, I had the same problem with my XT`s but I clean those once at month and never had that problem again

 

[gschuette]

How much ride time is on your brakes? Do you ride alot in the mud? If you have alot of time in the mud then you could have some crap in your system. You need to go to the bike shop and order some new pads, pistons, and square seals. The seals may come with the pistons I forgot. Pump all the fluid out of the system and you should be able to pull out the piston with some pliers. Clean out the inside of the system with alcohol to make sure the dirt is out. Put the seals on the pistons(it shows you how in the brochure that came with) Then push the pistons back in all the way(the new pistons not old) then bleed your system. The dirt inside attatches to the seal and the friction keeps you pads from retracting all the way. They end up getting closer and closer. The first post is normally a temporary fix, you will have to rplace pistons and seals if you want 100% drag free performance. Hayes brakes are a bitch to bleed so be careful not to get fluid on your new pads. Actually put your old pads in to bleed the brakes then when you are done clean the caliper with alcohol and then put in your new pads.

 

[pugslybell]

use a clean(very important) park cone wrench instead of rotor. Squeeze hard on lever with pads in. this will set the pads back further and more reliably then business cards.

 

[quickneonrt]

both of my brakes on my 03 bighit did the exact same thing. one side pretty much froze up on each caliper. changed the pistons and quad seals, bled them several times and nothing. had my lbs do it several times still nothing. sent them back to hayes waiting on a verdict.

 

[gschuette]

There are often burrs on the inside of where the piston moves. sometimes you can feel them with your bare hand. If so carefully file them off. then your new pistons and seals will work better.

 

[rfemurfx]

good god people!!! first lets start with the model of the brake. i will assume that it is and HFX-9 caliper. if your brake is under a year old and you can stand being with out it for a couple of weeks then do so and send it back to Hayes. they were some issues with the BORE(too small) of the caliper, and no matter how many times you do little tricks, replace pistons and quadrings they will never retract fully. if your brake perfomed fine until just recently then more than likely the cause of the problem is a misaligned caliper. why? beacuse if the caliper is not centered over the rotor one piston will move further than the other conciquently lubricating its quadring and having full retraction, while the other is not moving enough and then it gets STUCK! if that is the case then remove the wheel, with the pads still in the caliper squeeze the lever until the pads contact each other (make sure your pads are not totaly worn out) THIS WILL NOT ALLOW THE PISTONS TO FALL OUT! once they touch each other note the space that is left, if there is absolutely none then you have a bad caliper or hopefully bad pistons. replace pistons if you think that is the best way to go. the piston kit is sold per side and with a quadring. if you did end up withsome space and i mean constant space that by squeezing the lever normaly will not go away then reset the pistons (use the plastic wedge hayes provides with their brakes) gently squeeze the lever a small amount and notice if one piston moves more than the other, if one side stays stuck then remove the opposite pad and with a DH tire lever keep the piston whose pad you removed from moving. this will force the other side out and it will help lubricate the quadring. do this a few times. i know this sounds like alot but it works. then MAKE SURE YOU PROPERLY CENTER YOUR CALIPER WHEN DONE.

 

[oly]

A tip for removing the pistons if you decide to do a rebuild: (note, this can be messy, but if your rebuilding you might as make it easy, also wear plastic gloves.)

Remove pads and pump the lever a bunch of times. This will push the pistons quite a ways out of the caliper. Once you take the caliper bolts out you can easily remove them with a pair of pliers. Ive seen people try thr air gun nozzle to "pop" them out, but that doesnt always work, and you risk shooting fluid in your face. YOu cant usually pull the pistons out from full in either...it generally results in you tearing off the disk retainer tab. I know, ive done it.

The note about your caliper not being centered is a good one too. Are your pads worn uneven? That may also be a sign that things arent in line. Ask the LBS about a disk tab facing tool. Most frames arent very true to the wheel in respect to the disk tabs. Worth asking them to face if they can.

 

[caputo1989]

pop out the pistons and relube them with the hayes fluid. then re bleed them use as mutch fluid as posible.

 

[Brez]

Took a while to get registered but I made it finally.

I just wanted to say as my first post a big thanks to
rfemurfx. You nailed it as to what was wrong with my rear caliper. The front never gave me probs from day one but the rear was a different story. I came across your post here and it was excatly the problem. One piston was stuck and not moving at all.
The procedure you described loosened it up and did the trick.

Thanks again!