Kawasaki J300 - Service manual > Brake Disc

Brake Disc Removal

• Remove the wheels (see Front/Rear Wheel Removal in the Wheels/Tires chapter).
• Remove the brake disc mounting bolts [A], and take off the disc [B].
• Remove the wheel rotation sensor (speed sensor) rotor [C].
  • For rear wheel, the rear brake disc has the wheel rotation sensor only on ABS model.

Brake Disc Installation

• Installation is the reverse of removal.
• Apply a non-permanent locking agent to the threads of the brake disc mounting bolts.
• Tighten:
  Torque - Brake Disc Mounting Bolts: 34 N*m (3.5 kgf*m, 25 ft*lb)

Brake Disc Wear Inspection

• Measure the thickness of each disc [A] at the point where it has worn the most.

  If the disc has worn past the service limit, replace it.

  Measuring Area [B]

Brake Discs Thickness
 Standard:
  Front 3.8 - 4.2 mm (0.15 - 0.17 in.)
  Rear 5.0 mm (0.20 in.)
 Service Limit:
  Front 3.0 mm (0.12 in.)
  Rear 4.0 mm (0.16 in.)

Brake Disc Warp Inspection

• Raise the wheel off the ground with jack.

  Special Tool - Jack: 57001-1238

  • For front disc inspection, turn the handlebar fully to one side.
• Set up a dial gauge against the disc [A] as shown and measure disc runout, while turning [B] the wheel by hand.

  If runout exceeds the service limit, replace the disc.

Disc Runout
 Service Limit: TIR 0.4 mm (0.016 in.)

See also: