Yamaha YB50 Service Manual page 51

GENERAL OVERHAUL OF ENGINE
ENGINE REMOVAL ........................................................................4-1
REAR COVER AND FOOTREST PANEL ..........................................4-1
CARBURETTOR ........................................................................4-1
SILENCER ASSEMBLY ...............................................................4-1
CABLES AND TUBES ..................................................................4-2
REMOVAL OF ENGINE ...............................................................4-3
DISASSEMBLY THE ENGINE .........................................................4-4
REAR WHEEL ...........................................................................4-4
CENTRAL SUPPORT ..................................................................4-4
CYLINDER HEAD AND CYLINDERS .............................................4-4
PISTON PINS AND PISTON .........................................................4-4
KICK STARTER...........................................................................4-5
PRIMARY PULLEY WHEEL .........................................................4-6
SECONDARY PULLEY WHEEL ......................................................4-6
STARTER SYSTEM .....................................................................4-7
TRANSMISSION ........................................................................4-8
MAGNETIC FLYWHEEL ...............................................................4-8
AUTOLUBRICATION PUMP .........................................................4-9
CRANKCASE AND CRANKSHAFT ................................................4-9
INSPECTION AND REPAIR ............................................................4-11
CYLINDER HEAD .....................................................................4-11
CYLINDER AND PISTON ............................................................4-11
PISTON RINGS ........................................................................4-13
PISTON PIN AND PISTON PIN BEARING ....................................4-14
KICK STARTER ........................................................................4-15
TRANSMISSION........................................................................4-16
AUTOLUBRICATION PUMP.........................................................4-16
CRANKSHAFT ........................................................................4-16
PRIMARY PULLEY WHEEL .........................................................4-17
SECONDARY PULLEY WHEEL ...................................................4-18
TRAPEZOIDAL BELT ..................................................................4-19
GEARS AND STARTER CLUTCH ................................................4-19
ASSEMBLY AND ADJUSTMENT OF ENGINE .................................4-21
CRANKSHAFT AND CRANKCASE................................................4-21
AUTOLUBRICATION PUMP.........................................................4-23
FLYWHEEL MAGNET ...............................................................4-24
TRANSMISSION........................................................................4-25
STARTER MOTOR .....................................................................4-27
SECONDARY PULLEY WHEEL ...................................................4-29
PRIMARY PULLEY WHEEL .........................................................4-29
STARTER PEDAL .....................................................................4-30
PISTON AND PISTON PIN .........................................................4-35
CYLINDER AND HEAD
ENGINE ASSEMBLY ..................................................................4-38
CHAPTER 4
............................................................4-36
ENG