BSA D14/4 BANTAM SUPREME D14/4 BANTAM SPORTS, Руководство по ремонту

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D14/4 ELECTRICAL SYSTEM G11
A plug of the correct grade will bear a light flaky
deposit on the outer rim and earth electrode, and these
and the base of the insulator will be light chocolate
brown in colour. A correct choice of plug is marked
(
A ). ( B ) shows a plug which appears bleached, with a
deposit like cigarette ash ; this too is "hot-running" for
the performance of the engine and a cooler-running
type should be substituted.
A plug which has been running too "cold" and has
not reached the self-cleaning temperature is shown at
(
C ). This has oil on the base of the insulator and
electrodes, and should be replaced by a plug that will
burn off deposits and remove the possibility of a short-
circuit. The plug marked (
D ) is heavily sooted,
indicating that the mixture has been too rich, and a
further carburation check should be made. At
illustration (
E ) is seen a plug which is completely
worn out and in need of replacement.
To clean the plug it is preferable to make use of a
properly designed proprietary plug cleaner. The
makers instructions for using the cleaner should be
followed carefully.
When the plug has been carefully cleaned, examine
the central insulator for cracking and the centre
electrode for excessive wear. In such cases the plug
has completed its useful life and a new one should be
fitted.
Finally, before refitting the sparking plug the
electrode should be adjusted to the correct gap setting
of ·025" (·635 mm.). To prevent the possibility of
thread seizure occurring, it is advisable to clean the
threads of the plug with a wire brush then smear a
minute amount of graphite grease on to the threads.
If the ignition and carburation settings are correct
and the plug has been correctly fitted, but over-heating
still occurs, then it is possible that carburation is being
adversely affected by an air leak between the
carburetter and the cylinder. This possibility must be
checked thoroughly before taking any further action.
When it is certain that none of the above mentioned
faults are the cause of over-heating then the plug type
and grade should be considered.
Normally the type of plug quoted in General Data is
satisfactory for general use of the machine, but in
special isolated cases, conditions may demand a plug
of a different heat range. Advice is readily available to
solve these problems from the plug manufacturer who
should be consulted.
NOTE:—If the machine is of the type fitted with an
air filter or cleaner and this has been removed it will
affect the carburation of the machine.
HEADLAMP
Description
The headlamp glass, together with the reflector and
bulb assembly is secured to the main casing by means
of a slotted screw either above or below the lamp rim.
To gain access to the bulb therefore, it is only
necessary to loosen the screw until the rim can be
withdrawn.
To replace the double-filament bulb, press the bulb
retainer inwards and turn slightly anti-clockwise, to
release, enabling the bulb to be removed.
Replacement bulbs automatically provide correct
relationship of the filaments and focusing, therefore, is
unnecessary. Check the replacement bulb voltage and
wattage specification and type before fitting.