The front brake discs consist of an inner carrier, which is mounted to the wheel, and an outer rotor. Both parts must be changed together as a pair.
Remove the front wheel (sect. 7 - 1, Removal of the front wheel).
Undo the retaining screws (5) of the disc to the wheel, remove the disc (7) and, on its left side, slide out the phonic wheel (6).

Removal of the front brake system
Overhauling the front brake componentsRemoval of the gearbox assembly
Withdraw the selector fork shafts (30).
Move the forks (28) and (29) to disengage them from the slots in the selector
drum (14).
Withdraw the selector drum (16) taking care not to lose shims (31) and (27)
mounted on the shaft. Note that the
positions of the shims must not be inverte ...
Checking the engine timing
Set the engine to the configuration described for the "checking and adjusting
the valve clearances", previously indicated.
Install tool 88765.1188 (G) in the spark plug bore to determine the piston tdc,
the gauges (h) on the tool 88765.1518
And the timing check tool (degree wheel (l) 887 ...
Removing of the abs control unit
Drain the hydraulic fluid that is inside the front and rear braking system
tubes by disconnecting them from the master
cylinder and the calliper (sect. 4 -3, Changing the brake fluid).
Disconnect the connector (a) of the abs control unit (6).
Loosen the screws (16) that retain the abs ...