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INTRODUCTION 2
ENGINE TECHNICAL SPECIFICATIONS 4
SPECIAL EQUIPMENT 5
1 ENGINE REMOVAL FROM VEHICLE 6
2 ENGINE DISASSEMBLY 17
2.1 CLUTCH/GEAR OIL DRAIN........................................... 17
2.2 REMOVAL OF CLUTCH CONTROL ROD AND PINION
SPACER ........................................................................... 17
2.3 REMOVAL OF PISTON, CYLINDER AND HEAD ........18
2.4 REMOVAL OF IGNITION UNIT.....................................21
2.4.1 REMOVAL OF FLYWHEEL COVER ...........................................21
2.4.2 STATOR REMOVAL........................................................................ 21
2.4.3 REMOVAL OF FLYWHEEL...........................................................22
2.4.4 REMOVAL OF PICK-UP UNIT.................................................... 22
2.5 REMOVAL OF ELECTRIC IGNITION ............................ 23
2.5.1 REMOVAL OF START MOTOR................................................... 24
2.5.2 REMOVAL OF BENDIX COUPLING.........................................24
2.6 REMOVAL OF COOLANT LIQUID PUMP, CLUTCH
UNIT, MAIN GEAR, CENTRIFUGAL UNIT, GEARSHIFT
ORGANS, KICKSTART ...................................................25
2.6.1 REMOVAL OF COOLANT LIQUID PUMP .............................28
2.6.2 REMOVAL OF CENTRIFUGAL UNIT AND LEVERAGE ...... 29
2.6.3 DISASSEMBLY OF CLUTCH UNIT AND COUNTERSHAFT
COUNTERWEIGHT .......................................................................32
2.6.4 PEDAL KICKSTART - OPTIONAL...............................................35
2.6.5 EXTERNAL GEARSHIFT UNIT ...................................................37
2.7 INTAKE SYSTEM.............................................................38
2.8 CRANKSHAFT, GEARBOX UNIT AND INTERNAL
GEARSHIFT .....................................................................39
2.8.1 OPENING THE CRANKCASE .................................................... 39
2.8.2 COUNTERWEIGHT SUPPORT SHAFT....................................40
2.8.3 CRANKSHAFT.................................................................................40
2.8.4
INTERNAL GEARSHIFT UNIT AND COMPLETE GEARBOX
41
2.9 DISASSEMBLY OF PARTS FROM CRANKCASES.......43
2.9.1 RIGHT CRANKCASE HALF .........................................................43
2.9.2 LEFT CRANKCASE HALF.............................................................45
3 ENGINE CHECKS AND ASSEMBLY 46
3.1 CRANKCASE HALF.........................................................46
3.1.1 APPLICATION OF RIGHT CRANKCASE HALF PARTS........ 47
3.1.2 APPLICATION OF LEFT CRANKCASE HALF PARTS...........49
3.2 CONNECTING ROD AND ENGINE SHAFT CHECK...50
3.3 ASSEMBLY OF COMPLETE CRANKSHAFT ................51
3.4 GEAR UNIT: CHECKS AND REASSEMBLY .................52
3.4.1 GEARBOX UNIT CHECK ............................................................52
3.4.2 PRIMARY UNIT ASSEMBLY........................................................ 53
3.4.3 SECONDARY UNIT ASSEMBLY.................................................54
3.4.4 CHECKING THE FORKS, FORK PINS AND DESMODROMIC
DEVICE .............................................................................................55
3.4.5 GEARBOX AND INTERNAL GEARSHIFT ASSEMBLY.........57
3.4.6 COUNTERWEIGHT SUPPORT SHAFT....................................60
3.5 CLOSING THE ENGINE CRANKCASE ......................... 61
3.6 EXTERNAL GEARSHIFT.................................................62
3.6.1 CHECKING THE COMPLETE DRIVE SHAFT ........................62
3.6.2 EXTERNAL GEARSHIFT ASSEMBLY ........................................64
3.7 KICKSTARTER DEVICE - OPTIONAL............................65
3.7.1
CHECKING THE KICKSTART SHAFT UNIT AND ASSEMBLY ..
65
3.7.2 ASSEMBLY OF KICKSTARTER DEVICE....................................66
3.8 COUNTERWEIGHT, PRIMARY GEAR AND CLUTCH
UNIT.................................................................................68
3.8.1 INSPECTION OF COUNTERWEIGHT
AND PRIMARY GEAR...................................................................68
3.8.2 APPLICATION OF PRIMARY GEAR
AND COUNTERWEIGHT ............................................................68
3.8.3 CHECKING THE CLUTCH CASE, ROLLER BEARING AND
INTERNAL CENTRE BEARING.................................................. 70
3.8.4 CHECKING THE CLUTCH DISCS............................................. 71
3.8.5 CHECKING THE SPRINGS......................................................... 71
3.8.6 CHECKING THE CLUTCH DRUM AND CAP ....................... 72
3.8.7 CHECKING THE THRUST BEARING DEVICE...................... 72
3.8.8 CLUTCH UNIT ASSEMBLY.......................................................... 73
3.9
COOLANT LIQUID PUMP AND CENTRIFUGAL UNIT...
76
3.9.1 CHECKING THE PUMP UNIT AND DISASSEMBLY,
CENTRIFUGAL UNIT AND IDLER UNIT ............................... 77
3.9.2 CENTRIFUGE UNIT GROUP ASSEMBLY ............................. 78
3.9.3 PUMP UNIT ASSEMBLY ............................................................ 81
3.9.4 ASSEMBLY OF COMPLETE CLUTCH COVER AND
PUMP UNIT.................................................................................... 81
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