Use a gauge to measure the clearance between fork pin and the slot on the selector drum.
If the service limit is exceeded, determine which part must be replaced by comparing these dimensions with those of new components (sect. 3 - 1.1, Gearbox).
Also check the wear on the drum support pins; these must not show any signs of scoring, burrs, or deformation.
Turn the drum in the crankcase to establish the extent of radial play. If play is excessive, change whichever part is most worn.


Inspection of the gear selector forks
Reassembly of the gearbox shaftsRefitting the external components
Fit the cap (39) on spring (38) until it engages.
Mount ball (40), spring (38) with cap (39), washer (37) and screw (36) on the
chain side half-casing by starting the
screw into hole (f).
Note
The spring (38), with cap (39), must be oriented as shown.
Tighten the screw fully home to a torqu ...
Removing of the rear wheel
Place the motorcycle on the rear service stand and engage the 1st gear.
Remove the clip (6).
Using a suitable socket wrench, loosen the wheel nut (1).
Fully unscrew the nut (1), then remove the washer (2) and the spacer (3).
Remove the rear wheel from the motorcycle.
...
Refitting the timing covers
Locate vertical cylinder external cover (25), horizontal cylinder external
cover (3) and central external cover (1) by
starting the screws (4).
Apply the recommended threadlocker to the screws (4).
Tighten the screws (4) to a torque of 10 nm (min. 9 Nm - max. 11 Nm) (sect. 3 -
3, Engine t ...