Skip to content
HowDoIFix
All guides

Hydraulic disc brake caliper

Align a Hydraulic Disc Brake Caliper

Park Tool procedure for a rubbing hydraulic caliper. Loosen, squeeze, tighten — plus the diagnosis that tells you it is alignment, not a bent rotor.

easy5 steps15 minNot rated

Before you start

  • Do not true a rotor by bending it with the caliper. Align the caliper first.
  • Oil on pads is the end of those pads. Keep the hex off the rotor face.
  • Thru-axle bikes: the wheel must be fully seated before you align.

Tools

  • 4 mm or 5 mm hex
  • Work stand (optional)
  • Rotor truing fork (if the rotor is bent)

Parts

Caliper mount bolts · Brake pads · Rotor

  1. 01

    Decide: rotor or caliper

    Spin the wheel. If the rub is a once-per-rev tick, the rotor is bent — true it. If it hisses constantly, the caliper is off-center. This sheet is the constant hiss.

  2. 02

    Loosen the caliper bolts

    Crack both mount bolts just enough that the caliper can slide on the fork or adapter. Do not take them out. The hose should not have to twist.

  3. 03

    Squeeze and hold the lever

    Pull the brake lever and hold it. The pistons center the caliper on the rotor. Keep holding.

  4. 04

    Tighten while squeezed

    Still holding the lever, snug the two bolts evenly. Then release, spin, and listen. A remaining tick is rotor; remaining hiss is a sticky piston.

  5. 05

    Recheck at the axle

    Open and close the axle or QR, reseat the wheel, and spin again. Alignment is only true if it survives a wheel-out.

Was this accurate?

Rate the written steps, not the original video. One vote per browser.

Not rated