INDEX
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PREAMBLE 2
INFORMATIVE NOTE 2
SAFETY 2
SPECIAL EQUIPMENT 5
1 REMOVING THE ENGINE FROM THE VEHICLE 6
2 ENGINE DISASSEMBLY 15
2.1 THERMAL UNIT .............................................................15
2.1.1 CYLINDER HEAD: DISASSEMBLING MECHANICAL
TENSIONER ....................................................................................17
2.1.2 CYLINDER HEAD: DISASSEMBLING CAMSHAFT
SUPPORT, CHAIN GUIDE AND SPARK PLUG SEAT
O-RING ...........................................................................................18
2.1.3 CYLINDER HEAD: REMOVING CAMSHAFTS......................19
2.1.4 CYLINDER HEAD: UNCOUPLING FROM CYLINDER.......20
2.1.5 DISASSEMBLING CYLINDER AND PISTON.........................22
2.2 DISASSEMBLY OF IGNITION UNIT, TIMING CHAIN
AND GUIDES ..................................................................23
2.2.1 STATOR AND FLYWHEEL............................................................23
2.2.2 TIMING CHAIN AND GUIDES.................................................. 26
2.2.3 PICK-UP............................................................................................ 28
2.3 PINION AND SPACER ...................................................28
2.4 CLUTCH UNIT AND COOLANT PUMP COVER ..........29
2.5 ENGINE LUBRICATION CIRCUIT .................................33
2.5.1 OIL PUMPS CONTROL GEARS................................................ 34
2.5.2 HIGH-PRESSURE OIL PUMP....................................................34
2.5.3 LOW-PRESSURE OIL PUMP AND BY-PASS VALVE............35
2.5.4
OIL PRESSURE CONTROL VALVE ...............................................36
2.5.5
PAPER OIL FILTER..............................................................................36
2.6 COUNTERSHAFT ............................................................ 37
2.7
PRIMARY GEAR .................................................................38
2.8
ELECTRIC IGNITION ..........................................................39
2.8.1 ELECTRIC KICK-START UNIT .....................................................40
2.9
KICKSTARTER......................................................................41
2.10
EXTERNAL GEARSHIFT UNIT...........................................43
2.11
CRANKSHAFT, GEARBOX UNIT AND INTERNAL
GEARSHIFT .........................................................................44
2.11.1 NUT ON LEFT SIDE OF CRANKSHAFT.................................44
2.11.2
OPENING CRANKCASE...................................................................45
2.11.3
CRANKSHAFT .....................................................................47
2.11.4 INTERNAL GEARSHIFT UNIT AND COMPLETE GEARBOX ...47
2.12
DISASSEMBLY OF PARTS FROM CRANKCASES...........49
2.12.1
RIGHT CRANKCASE HALF ..............................................................49
2.12.1.1
PISTON OIL JETS.........................................................49
2.12.1.2
EXTRACTION OF COUNTERSHAFT SUPPORT
BEARING ........................................................................50
2.12.2
LEFT CRANKCASE HALF..................................................................50
2.12.2.1
INNER OIL FILTER.......................................................51
2.12.2.2
EXTRACTION OF DESMODROMIC DEVICE
BEARING ........................................................................51
3 ENGINE ASSEMBLY AND CONTROLS 52
3.1
CRANKCASE HALVES.........................................................53
3.1.1
EXTERNAL RIGHT SIDE ...................................................................54
3.1.1.1 INSERTION OF OIL SEAL AND COUNTERSHAFT
SUPPORT BEARING...................................................56
3.1.2
INTERNAL RIGHT SIDE....................................................................57
3.1.3
EXTERNAL LEFT SIDE.......................................................................58
3.1.4 INTERNAL LEFT SIDE .......................................................................59
3.2
CHECKING CRANKSHAFT AND CONNECTING ROD...60
3.3
ASSEMBLING COMPLETE CRANKSHAFT......................62
3.4
GEARBOX UNIT: CONTROLS AND REASSEMBLY ........63
3.4.1
CHECKING GEARBOX UNIT........................................63
3.4.2
PRIMARY UNIT ASSEMBLY.............................................................64
3.4.3
SECONDARY UNIT ASSEMBLY......................................................65
3.4.4
CHECKING THE FORKS, FORK PINS AND DESMODROMIC
DEVICE...................................................................................................66
3.5
ASSEMBLY OF INTERNAL GEARBOX AND
GEARSHIFT .........................................................................68
3.6
CLOSING ENGINE BLOCK ................................................71
3.7
BLOCKING THE CRANKSHAFT AT THE TOP DEAD
CENTRE AND TIGHTENING THE NUT ON THE LEFT
SIDE OF THE CRANKSHAFT.............................................72
3.8
EXTERNAL GEARSHIFT.....................................................73
3.8.1
CHECKING THE COMPLETE DRIVE SHAFT .............................73
3.8.2
ASSEMBLY OF EXTERNAL GEARSHIFT ......................................75
3.9
KICK STARTER ....................................................................75
3.9.1
CHECKING KICKSTARTER SHAFT UNIT AND ASSEMBLY ...75
3.9.2
ASSEMBLY OF KICKSTART DEVICE..............................................77
3.10
ELECTRICAL STARTER UNIT AND MAIN GEAR ............78
3.10.1
CHECKING ELECTRICAL STARTER DEVICE ELEMENTS .......78
3.10.2
COUPLING IGNITION AND PRIMARY GEARS TO THE
MOTOR ..................................................................................................79
3.11
OIL PUMPS: CONTROL AND REASSEMBLY .................81
3.11.1
ASSEMBLY OF LOW PRESSURE PUMP .....................................83
3.11.2
ASSEMBLY OF HIGH-PRESSURE PUMP AND CONTROL
GEAR ......................................................................................................84
3.11.3
CHECKING AND ASSEMBLY OF PRESSURE CONTROL
VALVE......................................................................................................85