Starting Failures/Incorrect Engine Idling Speed; Incorrect Engine Idling Speed; Engine; Fuel System - Yamaha YJ125S Service Manual

Ignition system
8Faulty C.D.I unit
8Faulty pickup coil
8Broken magneto rotor woodruff key
Switches and wiring
8Faulty main switch
8Faulty engine stop switch
8Broken or shorted wiring
8Faulty front and rear brake light switch
8Faulty start switch
8Faulty sidestand switch
8Improperly grounded circuit
8Loose connections
Starting system
8Faulty starter motor
8Faulty starter relay
8Faulty starting circuit cut-off relay
8Faulty starter clutch

INCORRECT ENGINE IDLING SPEED

STARTING FAILURES/
EAS00846
INCORRECT ENGINE IDLING
SPEED

ENGINE

Cylinder and cylinder head
8Incorrect valve clearance
8Damaged valve train components
Air filter
8Clogged air filter element

FUEL SYSTEM

Carburetor
8Faulty starter plunger
8Loose or clogged pilot jet
8Loose or clogged pilot air jet
8Damaged or loose carburetor joint
8Improperly adjusted engine idling speed
(throttle stop screw)
8Improper throttle cable free play
8Flooded carburetor

ELECTRICAL SYSTEMS

Battery
8Discharged battery
8Faulty battery
Spark plug
8Incorrect spark plug gap
8Incorrect spark plug heat range
8Fouled spark plug
8Worn or damaged electrode
8Worn or damaged insulator
8Faulty spark plug cap
Ignition coil
8Broken or shorted primary or secondary
coils
8Faulty spark plug lead
8Cracked or broken ignition coil
Ignition system
8Faulty C.D.I. unit
8Faulty pickup coil
8Broken magneto rotor woodruff key
8-2
TRBL
SHTG