Instruction manual

THE CLUTCH (See Illustration 17)

It should be noted that, although the basic design of the clutch fitted to 1951 models

is identical to the 1950 and earlier models, most parts have been revised in detail design,

and those parts are not interchangeable with those of previous years.

Clutch operating lever A is moved in direction of arrow to disengage the clutch.

Operation of clutch handlebar lever moves lever A in direction of arrow and causes it

to press against operating plunger B, which, in turn, presses against steel ball C, against

the clutch thrust rod D which pushes against the clutch spring pressure plate F.

This action compresses the clutch springs M so that their pressure is released from

compressing the clutch plain plates G and the clutch friction plates H, thereby allowing

the engine to drive the clutch sprocket L without imparting power, and motion, to the

gear box mainshaft T. Consequently no power is transmitted to the rear wheel and the

clutch is said to be " out " or free.

On allowing the clutch handlebar lever to return to its normal position the clutch operat-

ing lever becomes " free " and the clutch spring pressure causes the clutch thrust rod D,

the steel ball C and the operating plunger B to move to the right.

The whole of the clutch spring pressure is thereby transferred to the clutch spring pressure

plate F and this forces the steel plates G tightly against the clutch friction plates H so that

power, transmitted by the engine to clutch sprocket L, is transferred through clutch

case J to friction plates H, to steel plates G, to clutch centre E which causes the gear box

mainshaft to revolve.

Illustration 17

Showing clutch, gear box main shaft and clutch operating mechanism

CLUTCH SPRING ADJUSTMENT

If clutch slip is experienced the most probable cause is incorrect cable adjustment.

If the clutch cable adjustment is found to be correct, i.e., there is the clearance of Q inch

mentioned in the following paragraph, the clutch spring adjustment nuts should be adjusted.

To adjust clutch spring adjustment nuts :

Obtain access to clutch spring adjustment nuts by removing outer half of front chaincase.

Screw home one-half of a complete turn, each clutch spring adjustment nut and then test

for clutch slip.

If necessary, repeat, by screwing home a further half-turn but be careful to adjust each

of the nuts a similar amount.