Matchless G3L Maintenance Manual page 43

TRANSMISSION SERVICE
THE GEAR BOX
The gear box provides four speeds and has a positive foot change, operated by the right
foot and a kick-starter.
It is retained to the frame by being damped between the two engine rear plates by two
bolts. The bottom fixing bolt acts as a pivot. The top fixing bolt passes through the
gear box top lug and the rear plates, which are slotted, thereby allowing a swinging fore
and aft movement of the gear box to enable the front driving chain to be adjusted. That
movement is controlled by a bolt that has an eye encircling the gear box top fixing bolt
and which passes through an eye block secured to the right-hand side engine rear plate.
Two nuts threaded on the eye bolt, one on each side of the eye block, provide means of
accurately tensioning the front chain and, after that adjustment, locking the eye bolt
in its required position.
Illustration 14 clearly shows the general Internal gearbox layout, the simple gear
selection and kickstarter mechanism. It will be seen that movement of the foot change
lever causes movement of the cam barrel through the medium of an ingenious trip fork
to which the lever is attached.
This cam movement actuates the sliding gear striker forks causing movement of the
sliding gears which engage the stationary gears by dogs. As each gear is selected it is
held in engagement by means of a spring loaded conical ended plunger operating in
depressions on the end of the cam barrel.
The trip mechanism referred to allows the foot change lever to return to its normal
position, upon foot pressure being released, in readiness for the next change of gear.
Downward direction of movement causes engagement of higher gears and upward
movement with the toes causes a lower gear to become engaged.
As mentioned elsewhere an external marked disc shows at a glance which gear (or
neutral), is engaged.
The unusual method of clutch operation should be noted, the necessary thrust rod
movement to free being obtained through the medium of three balls operating on
inclined planes (see illustration 15).
Operation of the clutch handlebar lever moves clutch operating lever B causing inward
movement of the thrust rod by reason of the three balls mounting the inclined planes in
which they are located. The resulting inward movement of the clutch thrust rod forces
out the pressure plate, normally maintained in contact wit h the friction plates by the
springs E, thereby allowing the engine to drive the clutch sprocket D without imparting
drive to the mainshaft C.
Consequently no power is transmitted to the rear wheel, the clutch is said to be " out "
or " free." Upon releasing the clutch handlebar lever the clutch operating lever returns
to its normal position by the pressure of the spring forcing the balls down these inclined
planes thereby allowing the spring pressure through the medium of the pressure plate
to be transferred to the friction plates which causes the gear box mainshaft to revolve
and impart driving power to the rear wheel.
TO REMOVE KICK-STARTER CASE COVER FOR EXPOSURE
OF K.S., GEAR CHANGE A N D INTERNAL CLUTCH
ACTUATING MECHANISM
Remove oil drain plug and drain off oil contents of the gear box.
Remove the large oil filler plug and slack off the clutch cable adjuster sufficiently to
permit the cable end to be detached from the slotted end of the internal clutch operating
lever which is exposed by the removal of filler cap.
Unscrew the clutch cable adjuster until it is free from the K.S. case cover and withdraw
the cable nipple through the adjuster hole.
41