Rear brakes have become innefective

[ozstriker]

I am running an ultegra group set with 1100 k's on it and I have recently done a few long fast decents, and my rear brake has become almost completely useless.

Could I have glazed the pad, I have checked the rim and haven't noticed any oily residue on it, and my front brakes are still working relatively well?

Thoughts?

[Reman]

Try cleaning the rims with acetone or metho, I've found that helps remove any oily residue (especially what you can't feel).

Otherwise maybe dial out the levers so you get more leverage, or your brake cables have stretched and need to be reseated or replaced.

[R12RT]

You could try lightly sanding the pads.

I've had success with this in the past to improve brake performance.

[open roader]

You could try lightly sanding the pads.

I've had success with this in the past to improve brake performance.

+1

Sand them face down on some very fine emery paper and make sure the emery paper is dead flat to ensure an even cleaning. I'd also clean the brake track with metho or acetone.

[Stepr]

yeah reface the brake pads on a smooth file, and give the rims a going over with metho and 0000 (4 zero) steel wool lightly

[jacks1071]

You could try lightly sanding the pads.

I've had success with this in the past to improve brake performance.

A metal file is best for this - you can do it in the bike and it doesn't take much to take the glaze off.

I'd also wipe down the rims with metho or similar incase you've got oil or grease on them.

[jules21]

check that the pads are mating properly with the rim surface. as pads become worn, the caliper arc gets longer and this can result in the pads making contact with the rim lower down. if the bottom of the pad clears the rim braking surface, you'll get uneven pad wear and reduced braking performance.