KTM 50 SX 2017, Owner'S Manual

Page: 88 / 104

19 TROUBLESHOOTING
86
Faults Possible cause Action
Engine turns but does not start Operating error
–
Carry out the start procedure. ( p. 18)
Motorcycle was out of use for a long
time and there is old fuel in the float
chamber
–
Empty the carburetor float chamber.
Fuel supply interrupted
–
Check the fuel tank breather.
–
Clean the fuel tap.
(50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Spark plug oily or wet
–
Clean and dry the spark plug, or change it if
necessary.
Electrode distance (plug gap) of spark
plug too wide
–
Adjust the plug gap.
Guideline
Spark plug electrode gap
0.60 mm (0.0236 in)
Fault in ignition system
–
Check the ignition system.
Short circuit cable in wiring harness
frayed, kill switch defective
–
Check the kill switch.
The connector or ignition coil is loose
or oxidized
–
Clean the plug-in connection and treat it with
contact spray.
Water in carburetor or jets blocked
(50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Engine has no idle Idling jet blocked (50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Adjusting screws on the carburetor
are in turned to the wrong position (50 SX)
–
Carburetor - adjust the idle speed.
( p. 75)
(50 SX Mini)
–
Carburetor - adjust the idle speed.
( p. 76)
Spark plug defective
–
Change spark plug.
Ignition system defective
–
Check the ignition coil.
–
Check the spark plug connector.
Engine does not speed up The carburetor is flowing over
because the float needle is dirty or
worn (50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Loose carburetor jets (50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Fault in ignition system
–
Check the ignition system.
Engine has too little power Fuel supply interrupted
–
Check the fuel tank breather.
–
Clean the fuel tap.
(50 SX)
–
Check/set the carburetor components.
(50 SX Mini)
–
Check/set the carburetor components.
Air filter very dirty
–
Clean the air filter and air filter box.
( p. 48)