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After 20 years commuting on old/cheap bikes, I finally evolved up to a nice solid touring rig with cable disc brakes (Avid BB5). I love the bike and the brakes. They're much easier to maintain, replace, and adjust than my old rim brakes were (as a result, they are more effective more often).

However, recently I have been getting a periodic pad-on-disc noise that I have had difficulty getting rid of. After the pads have been used a while and are say 1/2 worn, they seem to "stick" so that some part of a pad is touching the disc. This is especially true after a session of braking hard (usually at the bottom of a hill). Sometimes I can knock them loose by braking again or tapping the brake levers hard, other times, even that doesn't work. Today, I actually dismounted and tried to work the pads apart by hand because the noise was really bugging me and I was worried that the disc would overheat.

Are those little springs that go between the pads the problem? Can I make them stronger somehow?

I've tried taking the springs out and bending them out before reinserting them, but no joy there either (at least not yet).

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The problem may be in in your cables. If the cables are dragging inside the housing the pads may not fully release. You can isolate the problem by disconnecting the cable from the brake. Then manually cycle the arm on the caliper. If it doesn't drag or stick after you release it, the problem is the cable. You can try lubing the cables it may help. It may also be time for new cables.Are you adjusting for pad wear with the cable adjuster or with the adjust screw on the caliper. If you are using the cable adjuster you may be pulling the caliper arm to the point of binding.

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Good suggestion. Definitely didn't consider the cables. The bike is ~3 years old and I think the cables should be fine. I might just disassemble them this weekend to see how things feel. I don't totally understand the adjustment question. There is what I would call a cable adjuster on the road side and a adjust wheel on the spoke side. I use them both depending on which pad appears to be the farthest from the disc when they feel like they need adjusting. When you say binding, do you mean sticking of the caliper arm? I don't think that is happening, but I'll look closer next time it happens. –  D. Woods Sep 28 '12 at 1:30
    
As the pads wear they get farther from the rotor. By adjusting the pad position screws on the caliper you are restoring the pads to their original position in relation to the rotor. The caliper arm retains its' home position at the start of it swing. If you adjust the pads by using the barrel adjuster on the brake lever, the caliper arm is moved away from the home position. When the brake lever is squeezed you potentially can move the lever past its' normal swing to the point that it will bind. –  mikes Sep 28 '12 at 3:02
    
makes sense. What is the right thing to do (or not do) to avoid it binding? FYI, I went out for a ride yesterday and don't think the caliper arm is sticking. –  D. Woods Sep 29 '12 at 20:28
    
Adjust for pad wear with the adjustment screws on the caliper. –  mikes Sep 29 '12 at 20:45
    
Yes, I do that. In a way, it seems like I'm causing the problem by adjusting the brakes. I don't think that is the case, but I can't figure out what else it might be. –  D. Woods Oct 16 '12 at 1:40
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