Assembling The Gearbox; Mainshaft Gears; Layshaft Gears - Triumph SPEED TWIN 1945 Workshop Instruction Manual

ASSEMBLING THE G E A R B O X
M a i n s h a f t Gears.
Secure the gearbox casing i n a vertical position w i t h the open
end facing upwards (See Fig.
26).
Slide t h e mainshaft third gear over the mainshaft
followed by t h e mainshaft second gsar, w i t h their selector grooves towards the centre.
Grease t h e camplate roller and
fit
it o n t o t h e smaller selector fork peg. Position
t h e smaller selector f o r k i n the second and t h i r d gear grooves w i t h the shaft o f the
selector f o r k below t h e mainshaft and t h e roller towards the clutch end of the casing.
Lower t h e assembly i n t o the case. W h e n the gear cluster i s correctly located, t u r n
t h e selector f o r k u n t i l the camplate roller rests i n the selector campiate track.
W i t h d r a w t h e mainshaft slowly, leaving t h e second and third gears and selector fork
i n position t o assist assembly of the layshaft gears.
L a y s h a f t Gears. Assemble the t h i r d and second gear w i t h the selector fork
grooves facing inwards t o tbe layshaft and high gear.
Apply grease t o the roller
and fit t o t h e larger selector fork peg.
Fit the larger selector fork i n t o the grooves,
with
t h e shaft o f t h e selector above the iayshaft and the camplate roller towards the
open end o f t h e gearbox. Lubricate t h e layshaft bush and lightly smear the shaft
w i t h oil. Lower t h e layshaf: assembly i n t o the gearbox, small gear first, until t h e
camplate r o l l e r can be engaged on the camplate track. O i l the selector rod and
thread
it
very carefully through the selector forks, shoulder end first, and engage
it i n the locating hole i n the clutch end o f the casing. O i l the mainshaft and thread
it
through t h e rnainshaft gears. Place the layshaft low gear over the layshaft end
with
t h e inrernal teeth facing inwards. Piace a strzight edge over the gearbox end
and test t h e clearance between the running face of the layshaft low gear and the
outer face o f the inner casing. Minimum allowable clearance i s 0.005" (0.13 mm.).
If t h e clearance is less than specified, t h e layshaft bush cannot have been fully located,
or, i f it has, t h e face of the bush must be cleaned up.
Remember that a layshaft
seizure means a locked rear wheel.
G e a r b o x I n n e r C o v e r . Fit the hollow dowels and long casing studs t o the casing
and lightly smear jointing compound o n t o the cover inner face. W i t h the selector
quadrant held i n t h e high (4th) gear position, assemble the inner cover t o the casing.
Tighten t h e casing screws ; do not o m i t t h e screw adjacent t o the selector quadrant
Inside the cover. The action of the seiector assembly can be checked if the qurdrant
i s operated by a screwdriver and the high gear and mainshaft are rotated at the same
time. Gear selection should be correct if these instructions have been carried o u t
correctly.
W i t h the selector i n high gear,
fit
the kickstarter ratchet and pinion assembly o n t o
t h e mainshaft i n the following order: plain washer, sleeve, spring, pinion w i t h ratchet
face facing outwards, ratchet, lockwasher and nut. Lock the gears by placing
a
block
between t h e chain sprocket and the vice and tighten up the ratchet nut. Bend the
locking washer tab over when the n u t is tight.
G e a r b o x O u t e r C o v e r . Smear jointing compound onto the face of the inner cover.
Grasp the gearchange pedal in one hand and the kickstart lever i n the other. W i n d
t h e kickstart pedal anti-clockwizr t o prevent the quadrant fouling the stop on the
inner cover, when the ouler :aver is slid i n t o position. Fit and tighten up the nuts