Ducati Scrambler 800 - Service manual > Clutch assembly: primary drive gears
Refitting the primary drive gears and checking backlash
Fully degrease the crankshaft splined end and the corresponding spline on the primary drive gear.
Check that tab and inner spacer are positioned on the crankshaft.
Fit the driving gear onto the crankshaft with the oil pump drive sprocket facing the crankcase.
Temporarily secure the gear with the washer (6) and ring nut (7).
To check the backlash, temporarily fit the clutch housing (1) complete with inner spacer (4), the driven gear (2), the roller bearing (3) and the inner race on the gearbox primary shaft.
Warning If fitting a new primary driving gear, check the backlash.
Fix a dial gauge to the crankcase, positioning the stylus against a gear tooth.
Turn the driven gear (2) to mesh the teeth and check that backlash ranges between 0.05 and 0.07 mm.
Repeat the check at 16 different points of the driven gear.
If the measured values are outside the tolerance limits, try changing the position of driven gear (2) on the primary shaft, leaving the driving gear (8) on the crankshaft in the same position.
If the backlash is still outside the tolerance limits, replace the complete primary drive gear (1).
After having checked the backlash, lock gear (8) using reaction tool no. 88713.2423, apply the specified grease on ring nut (7), and tighten it to a torque of 190 Nm (Min. 171 Nm - Max. 209 Nm).
Bend the washer (6) over ring nut (7).
Refit the oil pump and check the backlash between the oil pump gear and the primary drive gear on the crankshaft.
Thoroughly degrease the mating surfaces of the clutch housing (1) of internal bearing (3).
Insert inner spacer (4) inside primary shaft, with the flat side facing outside.
Fit the inner ring (5), the clutch housing (1) along with the driven gear (8) with needle bearing (3).
Refit the clutch unit (Refitting the clutch).
Refit the clutch cover (Refitting the clutch cover).
Fill the engine with oil (Changing the engine oil and filter cartridge).
Removing the primary drive gears
Drain the engine oil (Changing the engine oil and filter cartridge).
Remove the clutch cover (Removing the clutch cover).
Remove the clutch unit (Removing the clutch).
Remove the oil pump (Removing the oil pump).
Remove the clutch housing (1) complete with needle bearing (3) and primary driven gear (2).
Remove inner ring (5) and spacer (4).
Straighten out lock washer (6) on primary drive driving gear (8) fastening nut (7).
Lock the primary drive gear (8) with holding tool (A) no. 88713.2423 and loosen sprocket threaded ring nut (7).
Remove the nut (7) and the lockwasher (6).
Remove the primary drive driving gear (8) using puller (B) no. 88713.2092 and place between crankshaft and puller screw an aluminium or brass pad.
Pay attention to tab (9) positioned on the crankshaft and to the internal spacer.
See also:
Ducati Scrambler 800 - Service manual > Clutch assembly: clutch cover
Refitting the clutch cover Clean and degrease cover and casing mating surfaces. Check that the casing features the centring bushing (7).