Airburst

OK, I've got cable disc brakes on both my MTBs, and the front brake on one bike has lost a noticeable amount of stopping power recently. I had metallic pads in it until a few months ago, when they wore out and I replaced them with organic ones. They worked well for a while, but now the brake seems to be losing power. It's an Avid caliper, and it's always been fine before. What could be causing the problem?

By the way, I know I need hydraulic brakes, but the things cost 60 pounds each, and I'd need new shifters too, because my cable brake levers are integrated with my shifters. I'm on a fairly tight budget.

Thanks in advance

badamsjr

I have an Avid BB7 Road caliper on the front of my tourer (cable) and the original pads (semi-metalic) had good stopping power, but squealed, so I got some KoolStop organics, and they have nearly as much stopping power, with no squeal. When you "wore out" the metalic pads, was your rotor glazed? That might be an issue.

I had switched from V-brake to the disc to avoid the possibility of overheating the front RIM on long downhills while towing my loaded trailer, and while the 180mm rotor was adequate, it had no more power than the V-brake, so I changed to a 203mm rotor, and now it hauls me down in a hurry! Well worth the cost, plus added peace of mind.

Airburst

Well, the pads were worn down to within half a mm of the backing plate, so I figured that counted as "worn out". What do I use to remove the glaze on the rotor if it's glazed?

hockeyteeth

You can use rubbing alcohol to remove the glaze from the rotor. An alcohol-based degreaser like Speed Clean (made by Finish Line) works incredibly well for cleaning disc brake pads and rotors, in my experience. Simple Green is a great environmentally friendly degreaser that you can use to safely clean just about anything.

Adjusting mechanical disc brakes are especially tricky, but Avids are great and with patience you should be able to get them stopping great.

chewybrian 

I had a problem like this with the same brakes recently. It felt like I had no stopping power, but the handlebar lever was tight. It turned out that arm on the caliper was tapping out against the cable stop. To fix it, I had to release the cable, attatch it in a different spot, and re-adjust the calipers. Just look at the caliper as you squeeze the lever, and you can see if this might be happening.