Repair manual 250 / 300 / 380 Art No 3206004 -E
SERVICING ON INDIVIDUAL COMPONENTS
WORKING ON THE RIGHT-HAND HOUSING HALF . . . . . . . . . . . . . .5-2
WORKING ON THE LEFT-HAND HOUSING HALF . . . . . . . . . . . . . . . .5-3
CRANKSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4
CRANKSHAFT WEBS – MEASURE OUTER DIMENSION . . . . . . . . . . . .5-4
PISTON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4
PISTON RING END GAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4
CHECKING CYLINDER FOR WEAR . . . . . . . . . . . . . . . . . . . . . . . . . .5-5
RECOATED CYLINDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5
NIKASIL COATING OF CYLINDER . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5
CYLINDER EXHAUST CONTROL SYSTEM . . . . . . . . . . . . . . . . . . . . .5-6
CYLINDER PREASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6
EXHAUST CONTROL, CLUTCH COVER . . . . . . . . . . . . . . . . . . . . . . .5-8
PREASSEMBLY OF CLUTCH COVER . . . . . . . . . . . . . . . . . . . . . . . . .5-8
REED VALVE HOUSING, INTAKE FLANGE . . . . . . . . . . . . . . . . . . . . .5-9
CLUTCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-10
REPLACE OUTER CLUTCH HUB . . . . . . . . . . . . . . . . . . . . . . . . . . .5-11
SHIFT MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-12
PREASSEMBLY OF SHIFT SHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . .5-12
IGNITION (KOKUSAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13
SPARK PLUG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13
CHECK STATOR AND PULSE GENERATOR (KOKUSAN) . . . . . . . . . . .5-13
IGNITION (SEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-14
CHECK STATOR (SEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-14
TRANSMISSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15
ASSEMBLY MAINSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15
ASSEMBLY COUNTERSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-16
KICKSTARTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-17
ASSEMBLE OF KICKSTARTER SHAFT . . . . . . . . . . . . . . . . . . . . . . . .5-17
INDEX
5-1C
5
Engine housing
NOTE: Read through the following section before commencing work. Then determine the assembly sequence so that the engine
housing halves only need to be heated up once before replacing the bearings.
Having first removed the dowels, in order to expel the bearings or remove them with light mallet blows, the housing halves must be
placed on a suitably large plane surface, supporting the whole of the sealing surface without damaging it. A wooden panel is best
used as a base.
Bearings or shaft seal rings should not be hammered into their seats. If no suitable press is available, use a suitable mandrel and
hammer them in with great care. Cold bearings will practically drop into their seats at an engine housing temperature of approx.
150° C.
After cooling, should the bearings fail to lock in the bore, they are bound to rotate after warming. In that event the housing must
be replaced.