Bike Hydraulic Brakes constantly pressing against the rotor [duplicate]

Question

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• Hydraulic Disk brake piston not fully retracting 3 answers

I hope you can help me with this issue. My bike has Avid juicy 7 brakes, and lately both the front and the rear brakes are pressing against the rotor, which makes it really hard to ride it (feels like putting more resistance on a stationary bike). In the past before it got to this point the brakes randomly would be looser and then later more firm. Is it a bleeding issue or do you think that it's something else?

I would appreciate any suggestions. Thanks in advance!

Answer 1

There are a number of things this could be. Your rotors could be bent, your wheels could be improperly placed in the dropouts, your pads could be failing to contract, your brake calipers could be improperly adjusted, or your pad engagement point adjustment knobs could be failed or improperly adjusted.

It's likely not a bleed issue (brakes that need to be bled are generally "soft) unless someone injected enough fluid in your brakes to make them permanently partially contracted.

Your best bet is probably a trip to your LBS to get it sorted out. You could also try the assembly steps here (for your brakes) or find a resource that explains how to adjust hydraulic disc brakes.

Answer 2

Sram brakes always feels on and off, so there is nothing much you can do about it. Many of the sram users have reported that their brakes feels firm at one moment and the next moment, the brakes feels weak (no power).

Anyway, I am not sure if sram and shimano have the same piston set up/design. On the shimano brakes when my pads are rubbing against the rotor, I disassemble the piston and use something to push the pads back in. This allow more space for the rotor to move about.

Also, remember to check if your rotor is straight. I dont think bleeding has any effect with the problem you are facing.