Triumph Tigress TW2, Service Sheet

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SCOOTER SERVICE SHEET
1008
Printed January 1960
2 50 c.c. O.H.V. TWIN CYLINDER SCOOTER
ADJUSTMENTS WHICH CAN BE CARRIED OUT WITHOUT EXTENSIVE DISMANTLING
It is essential for the efficient running of the machine that certain checks are carried out periodically, in
accordance with the summary of routine maintenance laid down in the instruction manual.
On the left hand side of the machine is a nacelle with a wire mesh grill ; this is held in position by
one
A,"
screw on the right hand side, the left hand side being retained by a small lip behind the valance. Take
out the screw and remove by lifting the nacelle from the right hand side.
The circular contact breaker cover can now be seen situated to the right of the clutch~
operating lever. There is also a large hexagon plug which is the primary drive oil level and filler plug and
slightly to the right is a hexagon bolt fitted with a grease nipple to provide a means of greasing
the rear drive swinging arm bearing.
Contact Breaker.
The contact breaker gap'(A Fig. 4 Service Sheet No. 1004) when fully open should be between
0.14 and 0. 16".
To check the gap take out the two small screws which retain the circular contact breaker cover and
turn the engine over carefully until one of the fibre heels is on the peak of the cam, and the points
adjacent to this heel are fully open. This can be done either by placing the machine in gear and moving the
rear wheel or by gently turning the engine by means of the kick-starter.
If gap A is incorrect when the points are fully open, slacken the small circular nut B which will be
seen inside the C shaped coil of the spring, and the fixed contact point can then be moved in or out as
necessary. This is the contact point nearest the small condenser. When the gap is correct, retighten the
nut inside the C shaped spring and check again, re-adjusting if necessary.
Again turn the engine over until the other set of points is fully open and repeat the operation. When
both sets of points have been checked replace the cover by sliding the rubber grommet into the U shaped slot,
lift the black and white wire outside the left hand, long hexagon nut, to ensure that it does not foul the
cam when the engine is running and replace the contact breaker cover screws.
I g n i t i o n T i m i n g .
The normal ignition advance is 5 ° and the Scooter engine is very sensitive to ignition settings, only the
smallest deviation from the correct setting being sufficient to cause overheating and rough running.
The best way to check the timing is to observe the vanes on the cooling fan. These are spaced 11°
apart so that half the distance between two vanes is very near to 5 ° . The full procedure is, firstly, to rotate
the engine until the nearside piston is on top dead centre of the compression stroke (i.e., both valves closed).
Then turn the engine backwards through 5
° , remembering that it is a "backward-running" engine, and the
lower set of points (Fig. 4 Service Sheet No. 1004) should then be just breaking.
If the setting is incorrect slacken off the two long hexagon nuts which secure the contact breaker back
plate and rotate the plate until the points are just about to open. Then re-tighten the two hexagons and re-
check the adjustment.