Triumph Tigress TW2 Service Sheet Download

Page: 36 / 75

SERVICE SHEET

No.

1008

(contd.)

A certain amount of clearance or lost motion in the valve operating mechanism is esse~tial to ensure

that the valve heads close properly on their seats and provide a gas-tight joint.

The clearance of '005"

)(

for both inlet and exhaust valves is most critical and the Scooter engine is unlikely to run efficiently)J
there is any deviation from the standard

settings.,

The procedure for checking and adjusting

(which can be carried out with the valances in position]

is first to raise the dual seat and then to detach the sparking plug leads by placing the first two fingers
of the right hand beneath the plug terminal and pulling upwards with the thumb against the rocker
cover.

Next remove the two nuts which hold the rocker cover in position, swing the petrol tap support

bracket to one side and take off the steel and fibre washers from the two studs.

The rocker cover can

then be removed but care must be taken or the joint washer may be damaged.

Turn the engine by means of the kick-starter

or by rotating the rear wheel with.tpp .get{~4ngaged

until Valve No.1 (see diagram) is fully open.

Valve No.4 will then be in the correct-posit ion for check,ing'(

-~.

its clearance.

Check all the valves in this way in accordance with the table below by means of a ·0'05'"

feeler gauge i~se,rted between the end of the valve stem and the adjusting pin on the rocker.;."

''i--,~',

How to set the valves for checking clearances.

When No.1 Valve is fully open check No.4 Valve.

Note that this operation must be carried out when the

engine is cold.

When re-assembling

make sure that the washer i~i.P '

good condition before replacing the cover.

Use a new···J~;

if in doubt.

Carefully locate the cover over the two rocker

box studs and press it gently down making sure that

the

washer has not been misplaced.

Place the two fibre washers

and then the steel washers in position over the studs, swing
the petrol tap support bracket over the left hand side stud
and screw on the two

nuts.

Both nuts 'should be tightened a little at a time to ensure that the cover is not distorted and it may

also be necessary to support the petrol tap bracket to see that this is not twisted out of position for this
will affect the opening and closing of the petrol tap .

Fig. 27.~ Tappet adjustment.

. Sparking

phigs'.:f

It is essential for the efficient functioning of the engine that the sparking plugs are cleaned period-

isally at about 5,000 mile intervals and the gap between the plug terminals checked.

Cleaning is best

carrie~ out by a garage having the proper equipment,

the charge for this work being very moderate.

,.,.

The plug gaps can be checked and reset by the owner-rider, however.

To do this remove the plug

leads and unscrew the plugs with the~.spanner provided in the tool kit.

When lifting the plugs out be

ver.y careful not to drop the joinL\l.rashers as they will be impossible to retrieve without

removing all

the valances and the ducting round the engine.

The plug electrodes should be bright black in appearance and not' fouled with oil.

If they are whitish

in appearance

it is an indication of weak mixture and the cause of this should be ascertained

and be

eliminated.

In general it can be said that weak mixture can only be caused by a partial stoppage in the

carburetter, usually in the main jet. Correct spark plug setting is '018"- '020" and the setting should always
be corrected by bending the outside electrode ;in

no circumstances should th~ ~entre elect,rode be moved.