Royal Enfield CONSTELLATION 1958, Workshop Maintenance Manual

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crankcase pressure to the breather via the hole
drilled through the drive side main journal.
A plug screwed into the head of the bolt
retains the disc, and a hole drilled in its centre
allows the crankcase to breathe into the primary
chaincase.
A vent pipe fitted to the top of the primary
chain case has its aperture inside the case
shielded by a baffle from oil flung from the
chain. (See Fig. 8, Section C.)
18. Gearbox
The gearbox is bolted on to the back of the
crankcase and has four speeds, which are foot
controlled, and a patented neutral finder. All
gears are in constant mesh, changes being
effected by robust dog clutches. (See Section
E).
The standard gear ratios are as follows :-
Bottom Gear .......... ... ...... ... .. 12.35
Second Gear .......... ... ...... ... .. 8.16
Third Gear
.......... ... ...... ... .. 6.04
Top Gear ... ....... ... ...... ... .. 4.44
19. Clutch
The clutch has five pressure plates and four
friction plates, including the sprocket which is
lined on both sides with friction material. The
other friction plates have all Klingerite inserts
on early models.
Later models employ a different friction
material on the friction plate which is first in
order of assembly, to the following two plates.
These have a friction material of a corky
texture.
This assembly gives smooth operation, and
eliminates clutch slip under the most arduous
conditions.
The operating mechanism of the clutch is of
the latest Enfield design, which enables stronger
clutch springs to be used without increasing the
force required to operate it, thus giving
increased load carrying capacity to the clutch.
A description of the operating mechanism is
given in Section E, Sub-section 1.
Section B11 Page 4
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