6.3 -
1
2
3
4
5
6
Spare parts catalogue
Caution
Bold reference numbers in this section identify parts shown in this exploded view diagram. These parts do not appear in the figures near the text.
Disassembling the primary drive gears
 
Remove the clutch housing (1) together with needle roller bearing (3), inner ring (2) and driven gear of primary transmission (A).
Remove the inner spacer (4).
Unbend the safety washer (6) onto ring nut (5) securing the driving gear of primary transmission (B).
Hold the primary drive gear (B) using wrench part no. 88713.2423 and release the sprocket ring nut (5) using bush part no. 88713.2422.
Remove the ring nut (5) and the safety washer (6).
Remove the driving gear of primary transmission (B) using the puller part no. 88713.2092; fit an aluminium or brass plate between puller screw and crankshaft.
Do not damage the key (C) onto the crankshaft and the inner spacer.
Refitting the primary drive gears and checking meshing play
Degrease the taper end of the crankshaft and the mating surface on the primary drive gear accurately.
Check that the key (C) and inner spacer (D) are correctly fitted to the crankshaft.
Fit the driving gear (B) onto the crankshaft with oil pump control sprocket facing the casing.
Temporarily lock with the washer (6) and the ring nut (5).
Caution
If a new primary driving gear (B) is fitted, check its meshing play.
To check the meshing clearance, temporarily fit the clutch housing (1) together with inner spacer (4), driven gear (A), roller bearing (3) and inner ring (2), onto the gearbox primary shaft. Fix a dial gauge to the engine casing and place pointer tip in contact with a gear tooth.
Turn the driven gear (A) to match teething and check with the dial gauge that play ranges between 0.05 and 0.07 mm.
Repeat measurement at 16 positions of the driven gear.
If taken values are outside the allowed tolerance, change the position of the driven gear (A) onto the primary shaft leaving the driving gear (B) on the crankshaft untouched. If play is still outside the limits, change the primary drive gear pair (1).
When finished, fit bush part no. 88713.2422 to a torque wrench, hold sprocket (B) with wrench part no. 88713.2423 and tighten ring nut (5) to the specified torque (Sect. C 3, Engine torque settings).
Bend the washer (6) onto the driving gear (B) at milled zone and onto the ring nut (5) at a diametrically opposed position.
Refit the oil pump and check meshing play between oil pump gear and primary drive gear on crankshaft (Sect. N 2.1, Refitting the oil pump).
Carefully degrease the mating surfaces of clutch housing (1), inner bearing (3) and bush (2).
Slide the inner spacer (4) on the primary shaft with the flat side facing outwards. Fit the clutch housing (1) and the driven gear (A) together with needle roller bearing (3) and inner ring (2).