Supplementary - Triumph SPEED TWIN 1945 Workshop Instruction Manual

SUPPLEMENTARY INSTRUCTIONS
W i t h t h e exception o f the
3T engine, which w i l l be referred t o separately, t h e
instructions i n the main body of the Instruction Manual may be applied t o
a l l
machines
from 1945
to
the present day.
With t h e aid o f this supplement and t h e accompanying
data sheet, n o difficulty w i l l be found i n selecting the instructions for any individual
machine.
Some of the more important changes during this t i m e are as follows: The Mk. 1
spring wheel was introduced i n 1948 and together w i t h the Mk. 2 wheel, which
was introduced i n 1951. may b e fitted
to
any o f t h e rigid frame machines. A modified
gearbox was introduced i n 1950, w i t h the speedometer drive taken f r o m t h e timing
side end of the layshaft, and although
similar
i n construction the parts of the gearbox
are n o t interchangeable w i t h t h e previous model. W h e r e earlier models are fitted
w i t h a spring hub t h e speedometer drive
i s
taken from
a
pinion behind t h e final
drive sprocket.
Models previous t o 1949 have the orthodox telescopic fork, f o r which t h e servicing
instructions are the same
as
the Trophy fork i n the accompanying Instruction Manual,
b u t i n 1949 t h e nacelle was introduced containing
a 6"
diameter headlamp. Also
i n 1949 t h e o i l pressure gauge was dispensed with,
as
the instrument panel i n t h e
fuel tank was n o longer fitted, and an oil pressure indicator button on the timing
cover substituted. The r e t u r n o f t h e
oil
from t h e overhead rocker gear o n the
e l r l i e r models
i s
by internal o i l ways i n the cylinder head and block, b u t i n 1949
external oil drain pipes were fitted from the cylinder head t o the push r o d cover
tubes.
A n S.U. Carburetter was fitted t o t h e Thunderbird f o r 1952, and this necessitated
an eye i n t h e saddle tube for t h e air filter connection, this frame being used o n all
models up t o the introduction o f t h e swinging arm frame.
In
1952 t h e nacelle was
changed t o accommodate a
7"
diameter headlamp, incorporating
a
prefocus light
unit. A t the same time (from engine number 19706 N A ) t h e electrical system was
changed
t o
POSITIVE EARTH wiring.
Tappet Adjustment. A l l machines w i t h cast i r o n cylinder heads and barrels
previous t o engine number 37560 should be used w i t h a tappet clearance o f ,001"
(see page 37, para. a.), and machines w i t h alloy cylinder heads and barrels previous
to
engine number 37560 should be used w i t h a tappet clearance o f ,002" i n l e t and
.004" exhaust.
I n 1953 quietening ramps were added t o the camshafts, and a l l machines from engine
number 37560 w i t h an identification mark o n t h e drive side crankcase n e x t t o the
engine number, must be used w i t h tappet clearance of ,010". Use of a smaller
tappet clearance w i t h these particular camshafts w i l l result
in
t h e valves being b u r n t
out.
A major change t o o k place i n 1953 when the Speed T w i n was fitted w i t h t h e Lucas
RM.12 AC/DC lighting equipment. Following t h e experience gained w i t h this
generator t h e improved RM.14 type was fitted t o t h e Speed Twifi and also the
Thunderbird f o r t h e 1954 season.