My rear brake isn't working at all and i have no clue why. I took the wheel off and checked the pads, they looked fine. I cleaned them off with Comet and cleaned the rest of the brake assembly off with a degreaser. The springs are fine, the cable is hooked up perfectly. I squeeze the brake lever, and i see it pulling the brake, so i assume the pads are squeezing. but i can ride full speed with the brake clenched all the way. Any suggestions short of buying a new brake?