Honda CBF150 2002 Manual page 330

ENGINE LACKS POWER
1. Drive Train Inspection
Raise wheel off the ground and spin by hand.
Does the wheel spin freely?
NO
YES
2. Tire Pressure Inspection
Check tire pressure.
Are the tire pressures low?
YES
NO
3. Clutch Inspection
Accelerate rapidly from low to second.
Does the engine speed change accordingly when clutch is engaged?
NO
YES
4. Engine Condition Inspection
Accelerate lightly.
Does the engine speed increase?
NO
YES
5. Engine Condition Inspection
Accelerate or run at high speed.
Is there knocking?
YES
NO
6. Ignition Timing Inspection
Check ignition timing.
Is the ignition timing correct?
NO
YES
– • Brake dragging
• Worn or damaged wheel bearings
• Bent axle
– GO TO STEP 2.
– • Faulty tire valve
• Punctured tire
– GO TO STEP 3.
– • Clutch slipping
• Worn clutch discs
• Warped clutch plates
• Weak clutch spring
• Sticking clutch lifter mechanism
• Additive in engine oil
– GO TO STEP 4.
– • Fuel/air mixture too rich or lean
• Clogged air cleaner
• Restricted fuel flow
• Clogged muffler
• Clogged fuel fill cap breather
– GO TO STEP 5.
– • Worn piston and cylinder
• Use of poor quality fuel
• Excessive carbon build-up in combustion chamber
• Ignition timing too advance (Faulty ICM)
• Lean fuel mixture
– GO TO STEP 6.
– • Faulty ignition control module (ICM)
• Faulty ignition pulse generator
– GO TO STEP 7.
TROUBLESHOOTING
19-3