20 TROUBLESHOOTING
98
Faults
Possible cause
Action
Engine does not start
Operating error
–
Carry out start procedure. (
The motorcycle has been in disuse
for an extended period and old
fuel is in the float chamber
–
Empty the carburetor float chamber.
(
Fuel supply interrupted
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
Spark plug sooty or wet
–
Clean and dry the spark plug, or change it
if necessary.
Plug gap of spark plug too wide
–
Adjust plug gap.
Guideline
Spark plug gap
0.7 … 0.8 mm (0.028 … 0.031 in)
Fault in ignition system
–
Check the ignition system.
Magnetic switch cable in the
wiring harness chafed; magnetic
switch defective
–
Check magnetic switch.
Connector or ignition coil loose or
oxidized
–
Clean the connector and treat with con-
tact spray.
Water in carburetor or jets
blocked
–
Check/adjust the carburetor components.
The engine has no idle speed
Idling jet blocked
–
Check/adjust the carburetor components.
Adjusting screws on the carbu-
retor are in turned to the wrong
position
–
Carburetor
–
adjust the idle speed.
Faulty spark plug
–
Change the spark plug.
Faulty ignition
–
Check the ignition coil.
–
Check the spark plug connector.
Engine has too little power
Fuel supply interrupted
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
Air filter is very dirty
–
Clean the air filter and air filter box.
(
Exhaust system leaking or
deformed
–
Check exhaust system for damage.
Fault in ignition system
–
Check the ignition system.
Damaged membrane or reed valve
housing
–
Check the membrane and reed valve hous-
ing.
The engine stutters or there is
backfiring through the carburetor
Lack of fuel
–
Turn tap handle of the fuel tap to the
ON
position.
–
Turn tap handle of the fuel tap to the
RES
position.
–
Refuel. (
The engine takes in false air
–
Check the intake flange and carburetor for
firm seating.
Connector or ignition coil loose or
oxidized
–
Clean the connector and treat with con-
tact spray.