KTM 450 EXC USA Motorcycle User Manual


 
TROUBLESHOOTING 88
Faults Possible cause Action
Engine has a lack of power Air filter heavily contaminated
Clean the air filter. x ( p. 77)
Exhaust system leaky, deformed or
too little glass fiber yarn filling in
main silencer
Check exhaust system for damage.
Change glass fiber yarn filling of main
silencer. x
Valve clearance too little
Adjust the valve clearance. 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 stalls or pops back into the
carburetor
Lack of fuel Turn handle of the fuel tap to the ON posi-
tion. (Figure 500137-10 p. 22)
Refuel. ( p. 33)
The intake system has an air leak Check rubber sleeves and carburetor for tight-
ness.
Engine overheats Coolant level low in cooling system Check the cooling system for leaks.
Check the coolant level. ( p. 74)
Insufficient airflow Switch off engine when stationary.
Radiator fins very dirty Clean radiator fins.
Foam formation in cooling system
Drain the coolant. x ( p. 74)
Refill the coolant. x ( p. 75)
Bent radiator hose
Change the radiator hose. x
Thermostat defective
Check the thermostat. x
Guideline
Opening temperature: 70 °C (158 °F)
High oil consumption Engine vent hose bent Route the vent hose without bends or replace it
if necessary.
Engine oil level too high Check the engine oil level. ( p. 81)
Engine oil too thin (low viscosity) Change the engine oil and oil filter and clean
the engine oil screen. x ( p. 82)
Piston and/or cylinder worn Piston/cylinder - determine the mounting clear-
ance x
Battery discharged The battery does not charge
Check the charging voltage. x
Check the charging current. x
Check the generator. x
Undesired power consumer
Check the stall current. x
Speedometer values deleted (time,
stop watch, lap times)
The battery in the speedometer is
empty.
Change the battery in the speedometer.