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I just got delivery of a road bike with SRAM Red disc brakes. It was delivered with little inserts in the brake pads to prevent accidental squeezing of the lever when the rotor was not in.

When I put the wheels on, I noticed that the pads were too tight on the rotor even in the released position, so they were rubbing heavily (not because of misalignment but because of being too tight.)

So I did what I read online:

  1. Removed the wheel
  2. Removed the brake pads
  3. Gently used a flat-head screwdriver to push the pistons back in (the best I got was so that they were flush with the body of the brake caliper)
  4. Put the pads and wheel back on.

Unfortunately, when I squeezed the brake lever again, I could feel that the feeling got firmer and firmer for 2-3 squeezes, until, again, the brake pads would not recede from the "braking" position, and be in contact with the rotor at all times.

What can I do to fix this?

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    Are the pads actually in contact with the rotors now? Do the wheels spin freely? Hydraulic brake pads do not retract very much and may look like they are contacting the pads. – Argenti Apparatus Mar 22 at 23:12
  • Yes, it's a very heavy rubbing. The wheel won't spin half a turn if I push it with my hand. – Salvatore Iovene Mar 22 at 23:25
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    Try aligning the calipers? Also try riding the bike and doing the pad bed-in procedure. – Argenti Apparatus Mar 22 at 23:27
  • @ArgentiApparatus done that and didn't help. I even took it to a bike shop and they could not fix it! Said that the pistons will not recede properly after the brake levers are released. Sounds super weird to me, with brand new SRAM Red calipers. – Salvatore Iovene Mar 27 at 9:21
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    @SalvatoreIovene I've had 2 sets of Avid (SRAM) brakes fail this way, and my lbs gave the impression it is fairly common. Since yours is new, I would look to get the caliper replaced under warranty. – Andy P Mar 27 at 14:18
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My avid brakes had the same problem and it was due to too much fluid in the system, to solve the problem :

  1. Remove the pads and keep them away from any oil (fluid).

  2. Unscrew the bleed screw a little and put a towel on it

  3. Push the calipers back completely

4.Clean calipers well before reinstalling pads.

Be aware that the amount of fluid that will exit should be a drop or a little bit more. Let too much fluid exit and you will have to rebleed them, so do it gradually.

This is a common problem on new avid sram brakes.

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    +1 this is something I would try on my own bike, because I’m confident I could spot if I messed it up. Otherwise I’d have the shop do it. – Swifty Mar 27 at 20:14
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    Maybe suggest explicitly to remove the pads first of all and keep them away from any oil (fluid). Clean calipers well before reinstalling pads. – Swifty Mar 27 at 20:15
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    Thanks, I did exactly that. All it did is that now the brake lever needs to travel farther, in order to activate the pistons. But in the rest position they remain too tight and rub. – Salvatore Iovene Mar 28 at 9:23
  • @SalvatoreIovene if it didn't solve your problem you will probably have to go back to the shop that sold them to you and have them repair the brake(or replace them under warranty). – 1bikeForLife Mar 29 at 11:59
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It sounds like you reset the caliper piston correctly. Most hydraulics will automatically set the brake pad distance as you cycle the brakes. This is why it got firmer and started rubbing.

Next I would look at caliper alignment. Disc brakes have tight tolerances (i.e., the pistons only retract a short distance). If the caliper is not correctly aligned parallel to the rotor, part of the pad will touch the rotor, especially if the rotor isn’t perfectly true. Generally, you release the caliper fixing bolts, until the caliper can move, engage the brake firmly (to center the caliper on the rotor), then re-tighten to fixing bolts. Use a flashlight to check then alignment, there should be an even gap between the pad and rotor on all sides.

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