Ignition System; Poor Idle Speed Performance - Yamaha YP250 Service Manual

IGNITION SYSTEM

Battery
D Improperly charged battery
D Faulty battery
Fuse
D Burnt out, improper connection
Spark plug
D Improper plug gap
D Worn electrodes
D Wire between terminals broken
D Improper heat range
D Worn electrodes
D Faulty spark plug cap
Ignition coil
D Broken or shorted primary/secondary coil
D Faulty high tension cord
D Broken ignitin coil body
YP901000

POOR IDLE SPEED PERFORMANCE

POOR IDLE SPEED PERFORMANCE
Carburetor
D Loose or clogged pilot jet
D Damaged carburetor joint
D Improperly tightened carburetor joint clamp
hose
D Improperly adjusted idle speed
(Pilot screw), (Throttle stop screw), (CO test)
D Improperly adjusted throttle cable
D Flooded carburetor
Auto choke
D Faulty starter plunger
D Improper wax operation
D Faulty ignitor unit
D Faulty P.T.C. thermister
POOR IDLE SPEED PERFORMANCE
9-2
Ignition system
D Faulty ignitor unit
D Faulty pick up coil
D Broken magneto woodruff key
Switch
D Faulty main switch
D Faulty "ENGINE STOP" switch
D Faulty front and/or rear brake switch
D Faulty sidestand switch
Wiring
D Loose battery terminal
D Loose coupler connection
D Improperly grounded
D Broken wireharness
Air cleaner
D Clogged air cleaner element
Ignition system
D Faulty spark plug
D Faulty high tension cord
D Faulty ignitor unit
D Faulty pick up coil
D Faulty ignition coil
Valve system
D Improperly adjusted valve clearance
TRBL
SHTG