Chapter 6
(Power Transmission)
Final Drive
The final drive is devised as a pair of helical bevel gears housed in
a casing which serves at the same time as a plate for the brake
shoes, as an oil tank and a support for the right-hand end of the
rear wheel axle. The casing has an oil drain hole at the bottom
that is blanked off with a plug. Cover (Fig. 22, #34) attached to the
casing has a slot and two studs used to fasten the whole drive to
the swinging fork arm of the rear suspension. A hole is provided in
the cover for filling of oil.
Installed between the side portion of casing cover and the inner
race of ball bearing (Fig. 22, #36) is adjusting washer (Fig. 22,
#35) for adjusting the backlash between the gear teeth. For proper
performance of the drive a 0.1 to 0.3 mm / 0.004 to .012 in.
backlash is necessary between the active faces of gears.
CAUTION: Bearing nut (Fig. 22, #31) is left hand threaded.
Maintenance of propeller shaft and final drive.
The daily
maintenance involves tightening the nuts which fasten the final
drive to the swinging fork arm. Failure to tighten the nuts in due
time results in loose joints and destruction of the final drive cover.
Every 5,000 km change oil in the final drive casing. For this
purpose undo the filler and drain plugs and drain used oil. Fill the
casing with oil used for lubrication of the engine and flush the final
drive by turning the rear wheel several times. Drain oil and prime
the casing with 3.85 oz.of premium grade automotive 80/90w
Gearlube. Add friction reducing additive of choice.
Every 10,000 km, lubricate the needle bearings of the universal
joint cross. Dismantle the final drive and, using a grease gun, stuff
grease into the cross through the grease cup.
