STARTING FAILURE/HARD STARTING/POOR IDLE SPEED PERFORMANCE/POOR MEDIUM AND HIGH-SPEED PERFORMANCE

COMPRESSION SYSTEM

TRBL SHTG

Cylinder and cylinder head

Valve, camshaft and crankshaft

Loose spark plug

Improperly sealed valve

Loose cylinder head or cylinder

Improperly contacted valve and valve seat

Broken cylinder head gasket

Improper valve timing

Broken cylinder gasket

Broken valve spring

Worn, damaged or seized cylinder

Seized camshaft

Piston and piston rings

Seized crankshaft

Improperly installed piston ring

Worn, fatigued or broken piston ring

Seized piston ring

Seized or damaged piston

POOR IDLE SPEED PERFORMANCE

POOR IDLE SPEED PERFORMANCE Carburetor

Improperly returned starter plunger

Loose pilot jet

Clogged pilot jet

Clogged pilot air jet

Improperly adjusted idle speed (Throttle stop screw)

Improper throttle cable play

Flooded carburetor

Electrical system

Faulty spark plug

Faulty CDI unit

Faulty pickup coil

Faulty charging/rotor rotation direction coil

Faulty ignition coil

Valve train

Improperly adjusted valve clearance

Air filter

Clogged air filter element

POOR MEDIUM AND HIGH-SPEED PERFORMANCE

POOR MEDIUM AND HIGH-SPEED PERFORMANCE

Refer to “STARTING FAILURE/HARD STARTING” and “POOR IDLE SPEED PERFORMANCE-

VALVE TRAIN”.

Carburetor

Air filter

Improper jet needle clip position

Clogged air filter element

Improperly adjusted fuel level

Clogged or loose main jet

Deteriorated or contaminated fuel

10

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Yamaha LIT-11616-16-02, 5TE-F8197-10 service manual Compression System, Poor Medium and HIGH-SPEED Performance