Remove the seat and turn it upside down.
Loosen the special screws (4), turn the plates (5) and open the seat cover (2) lateral sides to slide it out.

Removal of the seat
Reassembly of the seatRoutine maintenance record
...
Checking valve clearances
To check the valves clearance, it is necessary to have access to the cylinder
head covers and then remove the
components listed below.
Unscrew the two fixing screws (1) of the cover (2) according to the
crankshaft.
Fit the tool handgrip 88713.0123 In the holes of the generator cover t ...
Adjusting throttle control free play
The throttle twistgrip must have free play of 1.5×2.0 Mm in
all steering positions, measured on the outer edge of the
twistgrip. If necessary, adjust it using the adjusters (1 and 2,
fig. 135) Located on the headstock on the right-hand side of
the vehicle.
Adjuster (1) is for throttle o ...