Yamaha XP500, Service Manual

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TRBL
SHTG
INCORRECT ENGINE IDLING SPEED/POOR MEDIUM-
AND-HIGH-SPEED PERFORMANCE/FAULTY CLUTCH
EAS00847
INCORRECT ENGINE IDLING SPEED
ENGINE
Cylinder(s) and cylinder head
• Incorrect valve clearance
• Damaged valve train components
Air filter
• Clogged air filter element
FUEL SYSTEM
Throttle body
• Damaged or loose throttle body joint
• Improperly synchronized throttle bodies
• Improperly adjusted engine idling speed
(idle adjusting screw)
• Improper throttle cable free play
• Flooded throttle body
• Faulty air induction system
ELECTRICAL SYSTEMS
Battery
• Discharged battery
• Faulty battery
Spark plug(s)
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
Ignition coil(s)
• Faulty spark plug lead
Ignition system
• Faulty ECU (engine)
• Faulty crankshaft position sensor
EAS00849
POOR MEDIUM-AND-HIGH-SPEED PERFORMANCE
Refer to “STARTING FAILURE/HARD STARTING”.
ENGINE
Air filter
• Clogged air filter element
Air intake system
• Clogged or leaking air duct
FUEL SYSTEM
Fuel pump
• Faulty fuel pump
EAS00853
FAULTY CLUTCH
ENGINE OPERATES BUT SCOOTER WILL
NOT MOVE
V-belt
• Bent, damaged or worn V-belt
• Slipping V-belt
Primary pulley cam and primary pulley
slider
• Damaged or worn primary pulley cam
• Damaged or worn primary pulley slider
Clutch spring(s)
• Damaged clutch spring
Transmission gear(s)
• Damaged transmission gear
CLUTCH SLIPS
Clutch shoe spring(s)
• Damaged, loose or worn clutch shoe spring
Clutch shoe(s)
• Damaged or worn clutch shoe
Primary sliding sheave
• Seized primary sliding sheave
POOR STARTING PERFORMANCE
V-belt
• V-belt slips
• Oil or grease on the V-belt
Primary sliding sheave
• Faulty operation
• Worn pin groove
• Worn pin
Clutch shoe(s)
• Bent, damaged or worn clutch shoe