Make the rear wheel turn until you find the position where chain is tightest. Set the vehicle on the side stand. Push down the chain at the point of measurement and release. Measure the distance between the "aperture" upper profile and pin centre.
The read distance must be: 9 to 11 mm.

Important
If the drive chain is too tight or too slack, adjust it so that tension reading will fall within specified range.
To adjust the tension remove the rear splash guard (sect. 7 - 13, Removal of the swingarm).
Slacken off the two clamp screws (1) that secure the rear wheel hub to the swingarm.
Fit the hook spanner code 88713.1038 Inserting its tooth in the eccentric hub (2).
Rotate the eccentric hub (2) to obtain the correct chain tension.
Turn counter clockwise to tighten the chain; clockwise to loosen (from chain side).
Important
An incorrectly tensioned chain will lead to accelerated wear of the transmission components.
If the screws (1) are removed, lubricate with specified grease underhead and thread, then tighten the screws (1) to the torque of 35 nm +/- 5% (sect. 3 - 3, Frame torque settings) proceeding with sequence 1-2-1.

Warning
The correct tightening of the fixing screws of the eccentric hub is essential for the safety of the rider and the passenger (sect. 3 - 3, Frame torque settings).
Refit the rear splash guard (sect. 7 - 13, Refitting the swingarm).
Adjusting the steering head bearings
Checking brake pad wear and changing brake padsRemoval of the clutch-side crankcase cover
Unscrew the screws (2), (3) and (5) securing the clutch-side crankcase cover
(1).
Tap around the edge of the cover with a plastic mallet to detach it from the
crankcase half.
Remove the clutch cover (1) paying attention to the centring bushing (12).
Check the condition of the cent ...
Gearchange mechanism
Return spring
Washer
Special screw
Gear pawl assembly
Interlock plunger holder
Sealing washer
Detent ball spring
Ball
Circlip
Selector claw return spring
Shim washer
Ring
Nut
Selector drum control fork
Gearchange lever pin
Shaft with gearchange lever arm
Gearch ...
Refitting the shock absorber support
If you had removed them, apply recommended grease on the threads of the
adjusters (4) and the ring nuts (3) having
care not to have grease on the surface (c) of the adjusters.
Tighten the adjusters on the ring nut side opposite to that featuring flats
until bringing the surfaces as close as ...