Brake Rotor, Weighing: Procedure

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-- Remove the front brake rotor to weigh it. Refer to FRONT BRAKE ROTOR, REMOVING AND INSTALLING .

-- Remove the rear brake rotor to weigh it. Refer to REAR BRAKES, CERAMIC, PR-1KU + PR-1KK .

Clean and dry the brake rotor before weighing it.

CAUTION: Never clean the brake rotor with water or any other fluid. This will make the measuring result incorrect.

NOTE:

The brake rotor vent holes must be free of dirt. It may be necessary to use something suitable to clean the holes.

Clean the brake rotor thoroughly with compressed air between the cooling channels and the vent holes.

-- Carefully lay the cleaned brake rotor on the scale.

The original weight of the new brake rotor and cup is engraved in the cup.

The following values have been determined as the lowest limit value for brake rotor loss in weight:

Front axle brake rotor: up to 120 grams weight loss from the original weight of the new brake rotor.
Rear axle brake rotor: up to 120 grams weight loss from the original weight of the new brake rotor.

NOTE: The limit values plus 20 grams are reached, then determine the brake wear by checking the wear indicators. Refer to WEAR INDICATORS, CHECKING .

If the limit values on the brake rotors are reached, then replace the brake rotors. The brake rotors can no longer be used. The brake rotor must be replaced.

Always replace the brake rotors on both sides of the axle when:

the brake rotors must be replaced because they are worn,
the replacement brake rotor has been technically modified, which can be determined by the revised part number.

In this case, replace the brake rotors on each side of the axle.

Brake pads likewise must always be replaced on both sides of the axle.