Honda CBR125R, Owner'S Manual

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TROUBLESHOOTING
21-3
ENGINE LACKS POWER
1. Drive Train Inspection
Raise wheel off the ground and spin it by hand.
Does the wheel spin freely?
NO – • Brake dragging
• Worn or damaged wheel bearings
• Bent axle
YES – GO TO STEP 2.
2. Tire Pressure Inspection
Check tire pressure.
Are the tire pressures low?
YES – • Faulty tire valve
• Punctured tire
NO – GO TO STEP 3.
3. Clutch Inspection
Accelerate rapidly, shift from first to second.
Does the engine speed change accordingly when the gearshift pedal is applied?
NO – • Clutch slipping
• Worn clutch discs/plates
• Warped clutch discs/plates
• Weak clutch spring
• Sticking clutch lifter mechanism
• Additive in engine oil
• Incorrect clutch lever adjustment
YES – GO TO STEP 4.
4. Engine Performance Inspection
Accelerate lightly.
Does the engine speed increase?
NO – • Dirty air cleaner
• Restricted fuel flow
• Clogged exhaust system.
YES – GO TO STEP 5.
5. Spark Plug Inspection
Remove and inspect spark plug.
Is the spark plug fouled or discolored?
NO – • Plugs not serviced frequently enough
• Incorrect spark plug heat range
• Incorrect spark plug gap
YES – GO TO STEP 6.
6. Engine Oil Inspection
Check oil level and condition.
Is there correct level and good condition?
NO – • Oil level too high
• Oil level too low
• Contaminated oil
YES – GO TO STEP 7.