Poor Running or No Power at High Speed:

Firing incorrect:

Spark plug dirty, broken, or maladjusted Stick coil wiring trouble

Stick coil not in good contact Spark plug incorrect Camshaft position trouble

IC igniter in ECU trouble Crankshaft sensor trouble Stick coil trouble

Fuel/air mixture incorrect:

Air cleaner clogged, poorly sealed, or miss- ing

Air cleaner O-ring damaged Air cleaner duct loose

Water or foreign matter in fuel Throttle body assy holder loose Fuel to injector insufficient (DFI) Fuel tank air vent obstructed Fuel line clogged

Fuel pump trouble

Compression low:

Spark plug loose

Cylinder head not sufficiently tightened down

No valve clearance Cylinder, piston worn

Piston ring bad (worn, weak, broken, or sticking)

Piston ring/groove clearance excessive

Cylinder head gasket damaged Cylinder head warped

Valve spring broken or weak

Valve not seating properly (valve bent, worn, or carbon accumulation on the seating surface)

Knocking:

Carbon built up in combustion chamber Fuel poor quality or incorrect

Spark plug incorrect

IC igniter in ECU trouble Crankshaft sensor trouble

Miscellaneous:

Throttle valve won’t fully open Brake dragging

Clutch slipping Engine overheating

Engine oil level too high Engine oil viscosity too high Drive train trouble

Air suction valve trouble Air switching valve trouble

Catalytic converter melt down due to muffler overheating (KLEEN)

Overheating:

Firing incorrect:

Spark plug dirty, broken, or maladjusted Spark plug incorrect

IC igniter in ECU trouble

Muffler overheating:

For KLEEN, do not run the engine even if with only one cylinder misfiring or poor running (Request the nearest service fa- cility to correct it)

For KLEEN, do not push-start with a dead battery (Connect another full-charged battery with jumper cables, and start the engine using the electric starter)

For KLEEN, do not start the engine under misfire due to spark plug fouling or poor connection of the stick coil

For KLEEN, do not coast the motorcycle with the ignition switch off (Turn the igni- tion switch ON and run the engine)

IC igniter in ECU trouble

Fuel/air mixture incorrect: Throttle body assy holder loose Air cleaner duct loose

Air cleaner poorly sealed, or missing Air cleaner O-ring damaged

Air cleaner clogged

Compression high:

Carbon built up in combustion chamber

Engine load faulty:

Clutch slipping

Engine oil level too high

Engine oil viscosity too high Drive train trouble

Brake dragging

Lubrication inadequate:

Engine oil level too low

Engine oil poor quality or incorrect

Gauge incorrect:

Water temperature gauge broken Water temperature sensor broken

Coolant incorrect: Coolant level too low Coolant deteriorated

Wrong coolant mixed ratio

Cooling system component incorrect:

Radiator fin damaged Radiator clogged Thermostat trouble Radiator cap trouble Radiator fan relay trouble Fan motor broken

Fan blade damaged Water pump not turning

Water pump impeller damaged