Ducati Diavel Workshop Manual page 754

Gearbox assembly: gearchange mechanism
must be screws of class 12.9 in order to respect the tightening torque indicated above (Sect. 3 - 3,
settings).
Start tightening the first screw (18), and continue with screw (20).
Remove service tool no.
Check that the pin (H) placed on the gear drum is axially to the notch (L) on the gear claw (with gear in neutral).
With the gearbox in neutral, check that the lever travel is the same when shifting up and down. The same should apply
when a gear is engaged.
Operate the gearchange lever and turn the front sprocket at the same time to check that all the gears engage when
shifting up and down.
Remove the previously installed lever and sprocket.
Operations
Refit the flywheel/alternator
Section reference
9 - 8, Refitting the flywheel-
Engine torque