KTM 450 EXC USA Motorcycle User Manual


 
TROUBLESHOOTING 87
Faults Possible cause Action
The engine cannot be cranked (elec-
tric starter).
Operating error Go through the steps of starting the engine.
( p. 31)
Battery discharged
Recharge the battery. x ( p. 69)
Check the charging voltage. x
Check the stall current. x
Check the generator. x
Fuse blown Remove the fuse. ( p. 70)
Install the fuse. ( p. 70)
Starter relay defective
Check the starter relay. x
Starter motor defective
Check the starter motor. x
Engine turns but does not start Operating error Go through the steps of starting the engine.
( p. 31)
Motorcycle was out of use for a long
time and there is old fuel in the float
chamber
Empty the carburetor float chamber. x
( p. 81)
Fuel supply interrupted Check the fuel tank breather.
Clean the fuel tap.
Check/adjust the carburetor components. x
Engine flooded Clean and dry the spark plug or replace if nec-
essary.
Spark plug oily or wet Clean and dry the spark plug or replace if nec-
essary.
Electrode distance (plug gap) of spark
plug too wide
Adjust the plug gap.
Guideline
Spark plug electrode gap
0.9 mm (0.035 in)
Defect in ignition system
Check the ignition system. x
Short-circuit cable in wiring harness
frayed, short-circuit button or emer-
gency OFF switch defective
Check the wiring harness. (visual check)
Check the electrical system.
Plug connector of CDI control device,
pulse generator or ignition coil oxi-
dized.
Clean the plug connector and treat it with con-
tact spray.
Water in carburetor or jets blocked
Check/adjust the carburetor components. x
Engine has no idle Idling jet blocked
Check/adjust the carburetor components. x
Adjusting screws on carburetor dis-
torted
Carburetor - adjust the idle speed. x
( p. 80)
Spark plug defective Change spark plug.
Ignition system defective
Check the ignition coil. x
Check the CDI controller. x
Check the spark plug connector. x
Check the ignition pulse generator. x
Check the generator. x
Engine does not speed up Carburetor running over because float
needle dirty or worn
Check/adjust the carburetor components. x
Loose carburetor jets
Check/adjust the carburetor components. x
Ignition system defective
Check the ignition coil. x
Check the CDI controller. x
Check the spark plug connector. x
Check the ignition pulse generator. x
Check the generator. x
Engine has a lack of power Fuel supply interrupted Check the fuel tank breather.
Clean the fuel tap.
Check/adjust the carburetor components. x