[Closed] Road disc pads too close .

Checked that the disc isn't warped / bent?

Are you Chris Froome? He thinks road disc pads are too close 😂

Has it worked fine before? Or is it new?

1) Undo the bolts on caliper, hold brake lever, tighten bolts, spin wheel. If that doesn't work.

2) check disc isn't warped

3) drop wheel out, remove pads, push pistons back, reassemble, pull brake, spin wheel. Check pads for uneven wear and replace if necessary.

4} no3 but with no1 before you pull brake.

5) if it still rubs, check pistons are moving freely, push them out slightly and clean, work them in and out. Make sure you don't have a lazy piston.

6) if still doing it, drop off at your LBS.

I’m not Chris Froome 😂, but I have sold a rim brake TCR SL and moved onto discs , Genesis Zero , 105 shifters and callipers , almost regretting it . Disc isn’t warped or bent and I’ve done all the centring stuff as above. Wandering if it could be a lazy piston as one of them seems to resist being pushed back , it’s not much but doesn’t take much , what can you do for a lazy piston ?

1) Undo the bolts on caliper, hold brake lever, tighten bolts, spin wheel. If that doesn’t work.

Don't do this.

Center the disk in the caliper. Don't center the disk between the pads.

Then sort out what the pistons are doing beyond that

If I bleed a little out out of the system will it help

Only if it's overfilled. I would basically follow Damascus's list except I would reset the pads with the reservoir open as a first step. Depending on the lever design, there must be a bleed port or some other way of opening the reservoir to allow excess fluid and air to escape when you bleed them. Position that so it's at the highest point in the system and open it. Then (with the wheel removed, obviously) gently push the pads apart with a flat screwdriver to force the pistons back into the caliper. If they have been overfilled, this will force any excess fluid out through the reservoir.

After that, loosen off the caliper mounting bolts, fit the wheel, and pump the brakes and hold them on. Then tighten the caliper bolts. This should center the caliper over the rotor. If the caliper is off-center, then you have a sticky piston.

After using all sorts of tools to move calipers I find the best tool is a wide plastic tyre lever, I have a park tool one with a bit of foam and tape over it. Paranoid about cracking a piston so I'm always careful. Sometimes they need a fair bit of force.

Don’t do this.

Center the disk in the caliper. Don’t center the disk between the pads.

I've always tried using the brake first to see if that works, if that fails then I do what @trail_rat says. I just find it hard to keep the caliper still while tightening it as usually the bolts are difficult to get to and only the slightest movement cocks it up.

Once it's tight, which ever method you use, just cast your eye over it when the wheel spins to make sure its centred and not rubbing. My old bb7s seemed like they needed tinkering with every few weeks on a commuter bike.

If I have a problemI do the loosen calipher,hold on brake then retighten but with the addition of a folded business card (or similar) over the disc between the pads. Always worked for me if I've had a problem.

I’ve bled the brakes and tried pushing pistons back in , the wheel is spinning freely now but there is no clearance between pad and disc , certainly couldnt fit a folded credit card in . Had a watch of a couple of YouTube vids showing cleaning the stuck pistons , will try this tomorrow .

Business card, not credit card. i.e. thin card.

I wouldn't expect sticky pistons to cause what you describe. Pistons are retracted by the rubber seal returning to its original shape. If the piston *doesn't* stick to the seal, it won't retract.

I have had this problem on SRAM brakes, with the brakes ratcheting on. Replacing the caliper seals fixed it.

is it both sides to close or just one? If just one try the hope method of centering. Video on their website

I wouldn’t expect sticky pistons to cause what you describe. Pistons are retracted by the rubber seal returning to its original shape. If the piston *doesn’t* stick to the seal, it won’t retract.

If one piston sticks, it doesn't extend properly. Then the other piston over extends and that side drags. Loosening off the caliper bolts, applying the brakes, then tightening the bolts is a workaround for this, but it will often leave the caliper off center.

I use a 0.6mm feeler gauge blade between the pad and disc instead of a piece of business card.

You can get little alignment tools for a few quid on Ebay.

I've got a Hayes alignment tool, does make adjusting brakes a bit easier.