Yamaha MX250 - Page 9

INSTALLING THE FLYWEIGHT
SHAFT ASSEMBLY AND
GOVERNOR FORK.............................3-19
ADJUSTING THE GOVERNOR ..........3-20
ENGINE SWITCH AND OIL WARNING
UNIT..........................................................3-21
CYLINDER HEAD COVER, CYLINDER
HEAD ........................................................3-22
CHECKING THE ROCKER ARM ........3-24
CHECKING THE PUSH ROD..............3-24
CHECKING THE CYLINDER HEAD ...3-24
INSTALLING THE CYLINDER HEAD
ASSEMBLY..........................................3-25
VALVE .......................................................3-26
REMOVING THE VALVES AND
VALVE SPRINGS.................................3-27
CHECKING THE VALVES AND
VALVE SPRINGS.................................3-27
CHECKING THE VALVE SEATS .........3-29
VALVE LAPPING .................................3-30
INSTALLING THE VALVES AND
VALVE SPRINGS.................................3-31
PISTON, CAMSHAFT, CRANKCASE,
AND CRANKSHAFT ................................3-32
REMOVING THE CAMSHAFT AND
VALVE LIFTER ....................................3-34
CHECKING THE CAMSHAFT.............3-34
CHECKING THE VALVE LIFTER ........3-35
INSTALLING THE VALVE LIFTER
AND CAMSHAFT ................................3-36
CHECKING THE CRANKCASE
COVER ................................................3-36
INSTALLING THE CRANKCASE
COVER ................................................3-36
CHECKING THE CYLINDER AND
PISTON ...............................................3-37
CHECKING THE CRANKCASE ..........3-38
CHECKING THE PISTON PIN ............3-39
CHECKING THE PISTON RINGS.......3-39
CHECKING THE CRANKSHAFT ........3-41
CHECKING THE CONNECTING
ROD OIL CLEARANCE .......................3-41
INSTALLING THE PISTON AND
PISTON RING .....................................3-42
INSTALLING THE CRANKSHAFT ......3-43
CARBURETOR
REMOVING THE CARBURETOR.............. 4-1
DISASSEMBLING THE CARBURETOR ... 4-2
CHECKING THE CARBURETOR ......... 4-3
ELECTRICAL
CIRCUIT DIAGRAM ................................... 5-1
ELECTRICAL COMPONENTS .................. 5-3
CHECKING THE SWITCH
CONTINUITY ........................................ 5-4
CHECKING THE IGNITION SPARK
GAP....................................................... 5-4
CHECKING THE SPARK PLUG CAP
RESISTANCE........................................ 5-5
CHECKING THE AIR GAP ................... 5-6
CHECKING THE IGNITION COIL
(TCI UNIT, PRIMARY) RESISTANCE ... 5-6
CHECKING THE IGNITION COIL
(TCI UNIT, SECONDARY)
RESISTANCE........................................ 5-7
CHECKING THE ENGINE SWITCH ..... 5-8
CHECKING THE OIL LEVEL
SWITCH................................................ 5-8
CHECKING THE WIRE HARNESS ...... 5-9
TROUBLESHOOTING
ENGINE DOES NOT START...................... 6-1
ENGINE STARTS BUT STALLS................ 6-2
ENGINE SPEED DOES NOT
INCREASE ................................................. 6-3
ENGINE SPEED IS UNEVEN .................... 6-4
GOVERNOR OPERATION......................... 6-5
SPECIFICATIONS
GENERAL SPECIFICATIONS ................... 7-1
MAINTENANCE SPECIFICATIONS .......... 7-3
ENGINE ................................................ 7-3