following conditions:
ASH
WHITE.
This
is
a sign that the plug is over-heating.
Usual cause is the mixture
strength too weak (a common cause being a faulty carburetter to cylinder head joint
or the ignition too far retarded.
DULL BLACK. This indicates that the plug is running too cold or, in other words
the insulator
is
insufficiently hot to burn off the carbon. This
is
caused by too rich
a mixture or the engine left r~nning with
a
generous slow running setting (quality
LIGHT BROWN.
This shows that the mixture strength is correct and the engine
is
running at the right temperature.
Before re-fitting the plugs, make sure that the copper washers ire not defective in
any way. If they have become worn and flattened,
fit
new ones to ensure that a
gastight joint is obtained.
&!
1
When installing plugs,
first
screw the plugs down by hand as far as possible, then use
i
k'
$
spanner for tightening only.
Always use a tubular box spanner to avoid possib!e
$
fracture to the insulator, but do not under any circumstances use a movable wrench.
i
;$
Paint splashes, accumulation of grime and dust etc.. on the top halfof the insulator are
1
gj
often responsible for poor plug performance.
Plugs should be wiped frequently
,g
.'
with a clean rag.
i
1
To save petrol and prevent difficult starring, plugs should be cleaned and tested at
regulai intervals, and
it
is
suggested that this service be performed at your garage on
I
a special "Air Blast" service unit.
Plugs which are allowed to remain oily and dirty
1
with corroded electrodes will seriously impair the efficient running of the motor
1
and waste precious petrol.
To obtain maximum efficiency from the engine and also to maintain good petrol
consumption which the motorcycle has when new, plugs should be changed at
,
!
regular intervals
as
old plugs are wasteful and cauze poor and sluggish running. We
recommend inspection, cleaning and testing every
3,000
miles
(5,000
kmr.), and
it
Will
be found economical
td
replace with new ones annually.
To Next Page
Loading...
Need help?
General
