A.J.S. 16 Instruction Book - page 38
Remove the bolt securing the automatic timing control to the cam wheel shaft.
Fit a 024328 withdrawal bolt in place of the fixing bolt removed which should be lightly
tightened.
A sharp blow on the end of withdrawal bolt will dislodge the unit from the
shaft.
Do not disturb the contact breaker cam.
Illustration 18
SETTING T H E I G N I T I O N T I M I N G
The maximum advance is 39° or ½" (12·7 mm.) before top dead centre, with the automatic
timing control wedged open to the
fully advanced
position.
Alternatively the firing point can be set with the piston 19° or
8
"
(3·175 mm.) before
top dead centre with the automatic timing device in the
fully retarded position.
To set the timing have available a stiff wheel spoke or similar object 5½" long.
Remove
H.T. cable and sparking plug.
„
Automatic timing control as already described.
„
The rocker box side cover.
Turn engine so that both valves are closed (inlet valve opens then closes) then engage
top gear.
Insert timing rod through sparking plug hole, feel piston by rocking engine forwards
or backwards by turning the rear wheel until it can be felt that the piston is at the extreme
top of its stroke with both valves closed.
Refer to illustration 19, and fit automatic advance control, with the gap formed by the
two bob weights in line with the two tapped holes, used to secure contact breaker plate.
It should be noted that the peak of the cam, or narrowest part, when correctly positioned
is approximately at 12 o'clock.
Press the unit firmly on to the shaft that drives it and give the end a sharp tap before
re-fitting the fixing bolt.
Insert a wood wedge between bob weights to fully separate
if fully advanced method is used.
36