Troubleshooting - KTM 450 EXC Owner's Manual

TROUBLESHOOTING

Faults
The engine cannot be cranked (elec-
tric starter).
Engine turns but does not start
Engine has no idle
Engine does not speed up
Engine has a lack of power
Possible cause
Operating error
Battery discharged
Main fuse blown
Starter relay defective
Starter motor defective
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 oily or wet
Electrode distance (plug gap) of spark
plug too wide
Defect in ignition system
Short-circuit cable in wiring harness
frayed, short-circuit button or emer-
gency OFF switch defective
Plug connector of CDI control device,
pulse generator or ignition coil oxi-
dized.
Water in carburetor or jets blocked
Idling jet blocked
Adjusting screws on carburetor dis-
torted
Spark plug defective
Ignition system defective
Carburetor running over because float
needle dirty or worn
Loose carburetor jets
Ignition system defective
Fuel supply interrupted
Air filter heavily contaminated
Action
–
Go through the steps of starting the engine.
( p. 31)
–
Recharge the battery. x
–
Check the charging voltage.
–
Check the stall current.
x
–
Check the generator.
x
–
Remove the main fuse. (
–
Install the main fuse. (
–
Check the starter relay.
x
–
Check the starter motor.
x
–
Go through the steps of starting the engine.
( p. 31)
–
Empty the carburetor float chamber.
( p. 85)
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
–
Clean and dry the spark plug or replace if nec-
essary.
–
Adjust the plug gap.
Guideline
Spark plug electrode gap
0.9 mm (0.035 in)
–
Check the ignition system.
–
Check the wiring harness. (visual check)
–
Check the electrical system.
–
Clean the plug connector and treat it with con-
tact spray.
–
Check/adjust the carburetor components.
–
Check/adjust the carburetor components.
–
Carburetor - adjust the idle speed.
( p. 84)
–
Change spark plug.
–
Check the ignition coil.
x
–
Check the CDI controller.
–
Check the spark plug connector.
–
Check the ignition pulse generator.
–
Check the generator. x
–
Check/adjust the carburetor components.
–
Check/adjust the carburetor components.
–
Check the ignition coil.
x
–
Check the CDI controller.
–
Check the spark plug connector.
–
Check the ignition pulse generator.
–
Check the generator.
x
–
Check the fuel tank breather.
–
Clean the fuel tap.
–
Check/adjust the carburetor components.
–
Clean the air filter. (
x
96
( p. 75)
x
p. 76)
p. 76)
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
p. 51)