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.

Remove the plug (3) and the O-ring (7), the engine oil pressure sensor (9) and its seal (8), the plug (16) and its seal (17) from the crankcase cover.

To check the condition of the oil sealing ring (6) installed in the crankcase cover between the clutch drum and the primary drive gear, first remove the latter two components (Sect. N 6.1, Removal of the clutch).

If the bush has been renewed, seat the new bush (10) in the clutch cover using a suitable drift or a press.

If the oil sealing ring (11) needs to be renewed, fit the new seal into the clutch cover, positioning it so the side without a spring is facing the circlip (13).

If it has been removed, install the new oil sealing ring (6) in the clutch cover, with the spring side facing inwards (see figure), and lubricate the seal lips with engine oil.

Fit the plug (3) and the seal (7). Fit the sensor (9) and the seal (8). Fit the plug (16) and the seal (17).

Clean and degrease mating surfaces on the clutch-side crankcase cover and crankcase half and ensure that locating bush (1) and the O-ring (2), located in correspondence with the oil way, are installed in the crankcase.

Lubricate the sealing ring (6) with engine oil and fit the bush 88700.5665 onto the primary drive gear so as not to damage the sealing ring while fitting the cover.

Tighten all the screws (5), (15) and (18) to the specified torque (Sect. C 3, Engine torque settings):