ABS components maintenance
7 -ABS components maintenance
Adjusting of the AIR-GAP phonic wheel sensor
(For front as well as rear sensor) In each case of maintenance that foresees:
- replacement or refitting of the wheel
- replacement or refitting of the phonic wheel (1) or (2)
- replacement or refitting of the brake discs
- replacement or refitting of the speed sensor (3) or (4)
- (front) replacement or refitting of the sensor holder bracket
- (rear) replacement or refitting of the calliper holder bracket
it is necessary to check the air-gap between the speed sensor and the phonic wheel, once the components are refitted.
Place the appropriate number of shims (B) under the ABS sensor so as to achieve 1.3 to 1.9 mm air-gap between ABS
sensor and phonic wheel. When shimming is correct, a 1.3 mm feeler gauge will fit between ABS sensor and phonic
wheel, whereas a 1.9 mm will not.
Check at three equally spaced locations (spaced about 120° apart) of the phonic wheels (1) and (2). Shims (B) come in
two sizes: 0.2 mm and 0.5 mm. Combine the shims as required to achieve correct shimming.
When checking with the 1.3 mm feeler gauge (go gauge) and the 1.9 mm feeler gauge (no-go gauge), the ABS sensors
(3) and (4) must be firmly secured in their seats. This means you need to loosen and retighten the sensor retaining screw
fully home with its washer each time you add or remove any shims.
Warning
For the front wheel ABS sensor (3), total shims used must never exceed 3 mm on the BASE version and 3.7 mm on the
CARBON version.
For the rear wheel ABS sensor (4), total shims used must never exceed 3 mm.
After shimming, tighten the retaining screws (5) and (6) of the sensors (3) or (4) to a torque of 10 Nm ± 10% (Sect. 3 -