How to Adjust an MTB Brake Rotor
- 1). Set your bike in a dedicated work stand or stationary trainer so you can spin the wheels of the bike. If neither of these are available, turn the bike upside down on its handlebars and seat so you can work.
- 2). Spin the first wheel slowly. Watch the rotor as it passes through the disk brake caliper. It can be helpful to hold a white index card or piece of paper behind the caliper to make imperfections easier to spot.
- 3). Find the first out-of-round spot on the rotor. Use a brake rotor tool to bend this spot on the rotor back into place. Do not be too forceful. You are trying to bend only this small area back into place.
- 4). Spin the wheel slowly and watch the rotor again. Find the next out-of-round spot on the rotor and straighten it in the same fashion as the first. Continue until the rotor spins as straight as you can make it through the caliper.
- 5). True the brake rotor of the second wheel in the same manner. When you are finished, take your bike for a test ride. The brake action should feel smoother and more responsive now that the rotors are in true.
