Honda CRF50F 2004-2015 Service Manual page 206

POOR PERFORMANCE AT LOW AND IDLE SPEED
1. Carburetor Air Screw Inspection
Check the carbureto r ai r screw adjustment.
Is the air screw correct?
NO - (page 5- ' 3)
YES - GO TO STEP 2.
2 . Intake Mantfold leaking Inspection
Check for leaks in the intake Manifold.
Is there Isaking?
YES _ . loose carburetor mounting
bolts
• Damaged insulator
NO - GO TO STEP 3.
3. Spark Test
Perform a spark t est.
Is
there
a
good spark?
NO _ . Faulty or fouled spark plug
• Faulty ignition con trol module
• Faulty ignition coil
• Broken or shorted spark plug wire
• Faulty engine stop switch or ignition switch
• Faulty ignition pu lse generator
• Loose or disconnected ignition system wires
YES - GO TO STEP 4.
4. Ignition Timing Inspection
Check th e ignition timing .
Is the Ignition timing normal?
NO - Improper ignition t iming (Faulty ignition control module)
POOR PERFORMANCE AT HIGH SPEED
1. Fuel line Inspection
Disconnect the fuel hose at the carburetor.
Does the fuel flow freely?
NO _ . Clogged fuel line
• Clogged fuel tank breather hose
• Faulty fuel valve
• Clogged fue l st rainer
YES - GO TO STEP 2.
2. Carburetor Inspection
Remove the carburetor and check for clogged jets.
Are the jets clogged?
YES -
Clean
NO -
GO TO STEP 3.
3 . Valve Timing Inspection
Check the valve timing.
Is the lIal1l8 timing correct?
NO - Cam sprocket not installed properly
YES - GO TO STEP 5.
4. Ignition Timing Inspection
Check the ignition timing.
TROUBLESHOOTING
16-5