Troubleshooting 19 - GAS GAS MC 85 2023 Owner's Manual

Faults
Engine turns but does not start
The engine has no idle speed
Engine does not speed up
Engine has too little power
Engine stalls or is popping into the
carburetor
Possible cause
Operating error
Motorcycle was out of use for a
long time and there is old fuel in
the float chamber
Fuel supply interrupted
Spark plug sooty or wet
Plug gap of spark plug too wide
Fault in ignition system
Short-circuit cable in wiring har-
ness frayed, stop button faulty
Water in carburetor or jets
blocked
Idling jet blocked
Adjusting screws on carburetor
distorted
Spark plug defective
Ignition system defective
Carburetor running over because
float needle dirty or worn
Loose carburetor jets
Fault in ignition system
Fuel supply interrupted
Air filter is very dirty
Exhaust system leaks, deformed
or too little glass fiber yarn filling
in main silencer
Fault in ignition system
Membrane or reed valve housing
is damaged
Lack of fuel
Engine takes in bad air
The connector or ignition coil is
loose or oxidized

TROUBLESHOOTING 19

Action
–
Carry out the start procedure. (
–
Empty the carburetor float chamber.
( p. 97)
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
–
Clean and dry the spark plug and spark
plug connector, or change if necessary.
–
Adjust plug gap.
Guideline
Spark plug electrode gap
0.60 mm (0.0236 in)
–
Check the ignition system.
–
Adjust the ignition system.
–
Check the stop button.
–
Check/set the carburetor components.
–
Check/set the carburetor components.
– Carburetor – adjust the idle speed.
( p. 96)
–
Change the spark plug.
–
Check the ignition coil.
–
Check the spark plug connector.
–
Check/set the carburetor components.
–
Check/set the carburetor components.
–
Check the ignition system.
–
Adjust the ignition system.
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
–
Clean the air filter and air filter box.
( p. 54)
–
Check exhaust system for damage.
–
Change the glass fiber yarn filling of the
main silencer. ( p. 55)
–
Check the ignition system.
–
Adjust the ignition system.
–
Check the membrane and reed valve hous-
ing.
–
Turn tap handle of the fuel tap to the ON
position.
–
Refuel. ( p. 27)
–
Check intake flange and carburetor for
tightness.
–
Clean the connector and treat it with con-
tact spray.
p. 24)
107