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 control unit
Loosen the screws (1) and remove the relay supporting bracket (2), disconnect
the connectors (3) and remove the control
unit (4) from the vehicle.
...
Topping up the electrolyte
Warning
Before carrying out any operations on the battery, keep in mind the
safety standards (sect.1 - 3, General safety rules).
The electrolyte in the battery is toxic and can cause burns if it comes into
contact with the skin because it contains
sulphuric acid. Wear protective clothing, a ...
Valves - rocker arms
Closing rocker arm shaft
Opening rocker arm shaft
Opening rocker arm
Closing rocker arm (left)
Valve opening shim
Half rings
Valve closing shim
Sealing ring
Valve guide
Exhaust valve seat
Exhaust valve
Plug
Intake valve seat
Intake valve
Aluminium gasket
Closing ...