19 Troubleshooting - GAS GAS MC 85 2021 Owner's Manual

19 TROUBLESHOOTING

Faults
Engine turns but does not start
Engine has no idle
Engine does not speed up
Engine has too little power
Engine stalls or is popping into the
carburetor
108
Possible cause
Operating error
Motorcycle was out of use for a
long time and there is old fuel in
the float chamber
Fuel feed interrupted
Spark plug oily or wet
Plug gap of spark plug too wide
Fault in ignition system
Short-circuit cable in wiring har-
ness frayed, switch-off 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 feed 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
Action
–
Carry out the start procedure. (
–
Empty the carburetor float chamber.
( p. 98)
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/set the carburetor components.
–
Clean and dry the spark plug, or change it
if necessary.
–
Adjust plug gap.
Guideline
Spark plug electrode gap
0.60 mm (0.0236 in)
–
Check the ignition system.
–
Adjust the ignition.
–
Check the switch-off button.
–
Check/set the carburetor components.
–
Check/set the carburetor components.
– Carburetor – adjust the idle speed.
( p. 97)
–
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.
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/set the carburetor components.
–
Clean the air filter and air filter box.
( p. 55)
–
Check exhaust system for damage.
–
Change the glass fiber yarn filling of the
main silencer. ( p. 56)
–
Check the ignition system.
–
Adjust the ignition.
–
Check the membrane and reed valve hous-
ing.
–
Turn handle of the fuel tap to the
ONposition.
–
Refuel. ( p. 28)
–
Check intake flange and carburetor for
tightness.
p. 25)