Check the cam contact surfaces for scratches, grooves, steps and waving.
Worn cams are frequently the cause of poor timing, which leads to loss of engine power.
Place the camshaft between two centres and check the run-out on the areas indicated using two dial gauges.
Service limit: 0.1 Mm.

Visually inspect the camshaft tracks for scoring and abnormal wear. If any of the above defects are found, the camshaft should be renewed.
If you find scoring or excessive wear, check the operation of the engine lubrication circuit.



Removal of the camshafts
Refitting the camshaftsGeneral safety rules
Carbon monoxide
When a maintenance operation must be performed with the engine running, maker
sure that the working area is wellventilated.
Never run the engine in an enclosed space.
Warning
Exhaust fumes contain carbon monoxide, which is a poisonous gas that
can cause unconsciousness or e ...
Removal of the throttle twistgrip
Peel back the rubber sleeve (a) protecting the throttle control cables.
Undo the screws (b) of the throttle grip (6) and open the command.
Disconnect the throttle grip cables (10) by unhooking the cable ends (c) from
their seats.
Remove the throttle twistgrip (6) from the handlebar.
...
Removing the frame and the lateral footrests
Loosen the two special screws (6) to separate the frame (1) from the lateral
brackets (2) and (3).
On the left side of the vehicle block retaining pins (9) and loosen the nuts (8)
on the right side at the same time.
Slide out the retaining pins (9) and remove the frame (1) from the lateral ...