How can I fix brake pads being too tight even after pushing the pistons back in?

Question

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:

Removed the wheel
Removed the brake pads
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)
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?

Rider_X · Answer

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.

1bikeForLife · Answer

My avid brakes had the same problem and it was due to too much fluid in the system, to solve the problem :

Remove the pads and keep them away from any oil (fluid). 
Unscrew the bleed screw a little and put a towel on it
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.

How can I fix brake pads being too tight even after pushing the pistons back in?

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