(For front as well as rear sensor) in each case of maintenance that foresees:
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 - 3, Frame torque settings) placing washers (7) and (8) in-between and check again using the 1.3 Mm feeler gauge (go gauge) and the 1.9 Mm feeler gauge (no-go gauge).


Phonic wheels cleaning
It is important to check that both phonic wheels (21) and (20) are always clean.
Otherwise: gently remove any possible dirt deposits with a cloth or metal brush. Avoid using solvents, abrasives and air or water jets directly on the phonic wheel (21) or (20).


Bleeding of the abs hydraulic systemEngaged gear indicator
This function displays the gears (1, fig. 25).
The instrument panel receives information and indicates the
engaged gear or "n" for neutral.
Note
In the case of a gear sensor "error", a dash "-" (not
flashing) will be displayed.
...
Refitting the rear wheel eccentric hub and rear wheel shaft
Refitting is the reverse of removal, with attention to the following points.
If the calliper bracket locating pin (14) was removed, apply the recommended
threadlocker on reassembly.
Tighten the pin (14) to the torque of 33 nm +/- 5% (sect. 3 - 3, Frame torque
settings).
If previously ...
Checking brake and clutch fluid level
The levels should not fall below the min marks on the
respective reservoirs.
If the level is too low, air can get into the circuit, thus
impairing the efficiency of the system.
Brake and clutch fluid must be topped up and changed at the
intervals specified in the scheduled maintenance table ...