Bicycles use various braking systems. Each system is designed to slow and control the bike effectively. A Hayes disc brake is a brand and design of brake that uses a caliper in combination with a rotor. Inside the caliper is a set of brake pads. As pads wear from use, the brake lever has to travel further in order for the pads to engage the rotor. Adjusting the gap between the pads and rotor helps compensate for wear.
Steady the bicycle against a stable surface or have someone hold the bicycle as the brake is being adjusted. The caliper is located on the left, or non-drive side, of the bicycle. Position the bicycle so that the left side is accessible.
Notice the pad adjuster on both sides of the Hayes disc brake caliper. Each adjuster has a bolt at the centre. Each adjuster is used to set the gap between one of the pads and the side of the rotor.
Turn the bolt on the outside adjuster clockwise to decrease the gap between the outside pad and the rotor. Set the gap for between 0.38 and 0.50mm. To check the gap, insert a feeler gauge of the recommended value between the pad and the rotor. Some resistance should be felt when moving the gauge back and forth between the pad and rotor.
Turn the bolt on the inside adjuster clockwise to decrease the gap between the inside pad and the rotor. Once again set the gap at between 0.38 and 0.50mm. Use the proper feeler gauge to measure the gap.
Spin the wheel slowly and check to make sure the pad is not rubbing the rotor. If the pad is rubbing the rotor, use the pad adjusters to decrease the gap slightly.