Bold reference numbers in this section identify parts not shown in the figures alongside the text, but which can be found in the exploded view diagram.

Unscrew the screw (17) and remove the oil breather valve (1) with the O-rings (2). Check the condition of O-rings (2) and renew them if necessary.

Remove the mesh filter (A) from the clutch crankcase half (Sect. 4 - 3, Changing the coolant).

Remove gear position sensor (4) by means of the tool number 88713.3407.

Check the condition of O-rings (22) and renew them if necessary.

Start the screw (25) with washer (26), and tighten it to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm) (Sect. 3 - 3, Engine torque settings).

Use a feeler gauge to check the clearance between the engine sensor (23) and the timing gear (13). The value must be between 0.6 and 0.8 mm.

Tighten the screw (17) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm) (Sect. 3 - 3, Engine torque settings).

Position the by-pass spring (7) on the nipple (6) and apply the recommended threadlocker to the end of the nipple to be screwed in the crankcase half. Screw oil filter cartridge fitting (6) fully into the crankcase half, positioning the spring in the seat between the two notches (A). Tighten the nipple to a torque of 42 Nm (Min. 38 Nm - Max. 46 Nm) (Sect. 3 - 3, Engine torque settings).

Fit the seal (9) on the oil drain plug (10). Position the seal that the side with the square edge (B) is facing the chain side crankcase half.

Clean the plug thread, apply a string of THREE BOND TB1215 along the plug thread spreading it by the entire circumference (360°).

Screw the exhaust plug (10) with relevant washer (9), and tighten it to a torque of 6 Nm (Min. 5 Nm - Max. 7 Nm) (Sect. 3 - 3, Engine torque settings).

Refit idle gear position sensor (4) by means of the tool number 88713.3407.

Refit the mesh filter (A) (Sec. 4 - 3, Changing the engine oil and filter cartridge).

Fit the stud bolts (5) on crankcase half, by applying sealant on the thread and tightening them to a torque of 30 Nm (Min. 28 Nm - Max. 32 Nm) (Sect. 3 - 3, Engine torque settings). Use the appropriate commercial tool for this operation.

If removed, apply prescribed threadlocker on the dowel (24), tighten the latter to the torque of 15 Nm (Min.13.5 - Max.16.5) (Sect. 3 - 3, Engine torque settings), insert the seal (3) on the service plug (8): the seal must be oriented so that the square edge faces the clutch-side crankcase half. Apply prescribed threadlocker on the plug thread (8), start it in the crankcase half and tighten it to a torque of 15 Nm (Min. 13 Nm - Max. 17 Nm) (Sect. 3 - 3, Engine torque settings).

When introducing the driven gear (B) check that the tongue (15) is correctly fitted on the timing system shaft, align the gear slot with the tongue matching the driving gear timing mark (A) with the gear (B).

On completion of the refitting operations, check that tab washer (12) is staked against nut (11) in such a way as to prevent the nut from working loose.

At this point, it is possible to remove the starter motor as described in Sect. 6 - 3, Starter motor.