If the play becomes excessive, difficulty will be experienced in changing gear, as
the clutch may not fully disengage, in which case the control should be adjusted as
explained below.
To adjust, release the locknut and holding it with a spanner unscrew the adjusting
pin with a screwdriver one or two turns. Still holding the locknut with a spanner,
screw the adjusting pin gently in until it is felt to meet some resistance. Then
unscrew it half-a-turn and holding it in this position retighten the locknut. If the
adjustment is correctly made in this manner, it will be found that there is a small
amount of free play at the clutch lever on the left handlebar before this is felt to take
up the spring pressure during the action of declutching.
The clutch operating mechanism should be greased at regular intervals to maintain it
in good condition (see Page 12).
Clutch Dismantling
Before dismantling the clutch, the primary chain case cover must be removed as
described under Front Chain on page 24. The clutch springs must be compressed by
pressing the outer plate inwards until the circlip retaining the spring pressure plate
can be removed. Care must be taken to see that the springs are properly compressed
as damage may result if they are released suddenly and the job is best accomplished
with the aid of special clutch spring compressing tool 61-3191. When the spring
pressure plate is removed the four plates carrying friction pads can be withdrawn,
together with their mating plain plates. If the pads are burnt or otherwise damaged,
the plates should be replaced.
Gearbox
The gearbox, although built in unit construction with the engine, is self contained
as regards lubrication. An engine oil of S.A.E. 40 grade (page 22) is used for
lubricating the gears and primary drive, but self-mixing engine oils must not be used.
To change the oil in the gearbox, remove drain plug
E
(Fig. 6) at the bottom of the
gearbox and drain out the old oil. Wash out the gearbox with flushing oil and refill
with new oil through filler hole
(Fig. 7) to the appropriate level.
The correct level is given by the screw
(Fig. 6) situated on the primary drive cover
behind the footrest. The screw is painted red for ease of identification and must be
removed when refilling the gearbox. Replenish until oil flows from the level screw
hole and when any surplus oil has drained off, replace the screw firmly, followed by
These are fitted with ball journal bearings, and no adjustment is either provided or
The unit requires no attention apart from lubrication at intervals (see page 12)
