4.3 brakes

Rotor Truing

A bent rotor rubs the pads even with the lever released, creating drag and noise.

Difficulty ★★☆ moderate
Time ~10 min
Applies to All bikes with disc brakes

A bent rotor rubs the pads even with the lever released, creating drag and noise.

Tools

  • Rotor truing fork (Park DT-2)
  • or improvised with an adjustable wrench

Procedure

  1. Spin the wheel

    and watch the rotor pass through the brake caliper.

  2. Identify where the rotor rubs

    — look for which side of the caliper it touches and at what part of the rotation.

  3. Mark the bent section

    with a marker or tape on the rim adjacent to it (so you can find it once you stop spinning).

  4. Place the truing fork

    on the bent section, with the rotor in the slot of the tool.

  5. Bend gently

    in the opposite direction of the deflection. Small movements — a few millimeters of bend at a time.

  6. Spin and re-check

  7. Repeat until the rotor passes cleanly

    through the caliper without rubbing.

  8. For severe bends

    sometimes a rotor cannot be saved. If you can see a sharp crease or the rotor wobbles by more than 2 mm at the edge, replace it.

Touch only the rotor's brake track with the truing fork — keep your fingers off the brake surfaces (skin oils contaminate them).