How to Repair Bicycle Brakes
- 1). Use a 5 mm Allen wrench (the tip has a hex-head shape) and loosen the brake cable pinch bolt. This bolt is located on the side of the brake and secures the cable to the brake.
- 2). Squeeze the sides of the brake so that the brakes pads (there's one on each side) press against the sides of the rim. Each pad should strike the center of the rim. If either pad is striking the rim above or below this point, see Step 3. If pad height is fine, proceed to Step 4.
- 3). Use the 5 mm Allen key and loosen the bolt at the back of the appropriate pad. The loosened pad can now be raised or lowered as needed. Once proper height is achieved, re-tighten the bolt.
- 4). Turn the brake cable adjusting barrel all the way in toward the body of the brake. Depending on model bike, this barrel will be located where the cable first enters the brake or where the cable enters the brake lever.
- 5). Remove all slack from the cable, grabbing the end with needle-nose pliers, and pulling. While pulling, use the Allen wrench to re-tighten the pinch bolt onto the cable.
- 6). Turn the brake cable adjusting barrel away from the brake (counterclockwise) until each brake pad sits three to four millimeters from the side of the rim. Each turn of the adjusting barrel in this direction will cause the pads to move closer to the rim.
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