CRANKSHAFT/TRANSMISSION 9-1

Crankshaft/Transmission

Table of Contents

Exploded View...................................	9-2
Specifications ....................................	9-6
Special Tools and Sealants ...............	9-9
Crankcase .........................................	9-11
Crankcase Splitting ......................	9-11
Crankcase Assembly ...................	9-12
Crankshaft and Connecting Rods......	9-17
Crankshaft Removal ....................	9-17
Crankshaft Installation .................	9-17
Connecting Rod Removal ............	9-18
Connecting Rod Installation .........	9-19
Crankshaft/Connecting Rod
Cleaning ....................................	9-22
Connecting Rod Bend Inspection	9-22
Connecting Rod Twist Inspection.	9-23
Connecting Rod Big End Side
Clearance Inspection ................	9-23
Connecting Rod Big End
Bearing Insert/Crankpin Wear
Inspection..................................	9-23
Crankshaft Side Clearance
Inspection..................................	9-25
Crankshaft Runout Inspection......	9-25
Crankshaft Main Bearing
Insert/Journal Wear Inspection .	9-26
Pistons...............................................	9-28
Piston Removal............................	9-28
Piston Installation.........................	9-29
Cylinder (Upper Crankcase) Wear
Inspection..................................	9-30
Piston Wear Inspection ................	9-30
Piston Ring, Piston Ring Groove
Wear Inspection ........................	9-30
Piston Ring Groove Width
Inspection..................................	9-31
Piston Ring Thickness Inspection	9-31
Piston Ring End Gap Inspection ..	9-31

Starter Idle Gear and Starter Clutch ..	9-32
Starter Idle Gear Removal ...........	9-32
Starter Idle Gear Installation ........	9-32
Starter Clutch Removal................	9-34
Starter Clutch Installation ............	9-34
Starter Clutch Disassembly..........	9-34
Starter Clutch Assembly ..............	9-35
Starter Clutch Inspection..............	9-35
Transmission .....................................	9-37
Transmission Assy Removal........	9-37
Transmission Assy Disassembly .	9-37
Transmission Assy Assembly ......	9-37
Transmission Assy Installation.....	9-39
Transmission Shaft Removal .......	9-40
Transmission Shaft Installation ....	9-40
Transmission Shaft Disassembly .	9-40
......Transmission Shaft Assembly	9-40	9
Shift Drum and Fork Removal......	9-44
Shift Drum and Fork Installation...	9-44
Shift Drum Disassembly...............	9-44
Shift Drum Assembly ...................	9-44
Shift Fork Bending Inspection ......	9-44
Shift Fork/Gear Groove Wear
Inspection..................................	9-44
Shift Fork Guide Pin/Drum
Groove Wear Inspection ...........	9-45
Gear Dog and Gear Dog Hole
Damage Inspection ...................	9-45
External Shift Mechanism..................	9-46
Shift Pedal Removal ....................	9-46
Shift Pedal Installation .................	9-46
External Shift Mechanism
Removal ....................................	9-47
External Shift Mechanism
Installation .................................	9-47
External Shift Mechanism
Inspection..................................	9-48

9-2 CRANKSHAFT/TRANSMISSION

Exploded View

CRANKSHAFT/TRANSMISSION 9-3

Exploded View

	No.	Fastener		Torque		Remarks
			N·m	kgf·m	ft·lb
	1	Bearing Holder Screws	4.9	0.50	43 in·lb	L
	2	Breather Hose Fitting	15	1.5	11	L
	3	Breather Plate Bolts	9.8	1.0	87 in·lb	L
	4	Connecting Rod Big End Nuts	see the text	←	←	MO
	5	Crankcase Bolt (M8, L = 90 mm)	27	2.8	20	S
	6	Crankcase Bolts (M8, L = 95 mm)	31	3.2	23	MO, S
	7	Crankcase Bolts (M8, L = 75 mm)	27	2.8	20	S
	8	Crankcase Bolts (M6, L = 65 mm)	12	1.2	106 in·lb	S
	9	Crankcase Bolts (M6, L = 50 mm)	12	1.2	106 in·lb
	10	Oil Jet Nozzles	2.9	0.30	26 in·lb
	11	Oil Passage Nozzle	4.9	0.50	43 in·lb
	12	Oil Passage Plug	17	1.7	13
	13	Oil Passage Plugs (Taper)	20	2.0	15	L
	14	Race Holder Screws	4.9	0.50	43 in·lb	L
	15	Transmission Case Bolt (M6)	9.8	1.0	87 in·lb
	16	Transmission Case Bolts (M8)	20	2.0	15

17. Do not apply any grease or oil. EO: Apply engine oil.

G: Apply grease.

L: Apply a non-permanent locking agent. LG: Apply liquid gasket.

MO: Apply molybdenum disulfide oil solution.

(mixture of the engine oil and molybdenum disulfide grease in a weight ratio 10:1)

R:Replacement Parts

S:Follow the specified tightening sequence.

SS:Apply silicone sealant.

9-4 CRANKSHAFT/TRANSMISSION

Exploded View

CRANKSHAFT/TRANSMISSION 9-5

Exploded View

	No.	Fastener		Torque			Remarks
			N·m	kgf·m	ft·lb
	1	Gear Position Switch Screws	2.9	0.30	26	in·lb	L
	2	Gear Positioning Lever Bolt	12	1.2	106 in·lb
	3	Idle Gear Cover Bolts	9.8	1.0	87	in·lb
	4	Shift Drum Cam Holder Bolt	12	1.2	106 in·lb		L
	5	Shift Lever Bolt	6.9	0.70	61	in·lb
	6	Shift Pedal Mounting Bolt	25	2.5	18		L
	7	Shift Shaft Return Spring Pin	28	2.9	21		L
	8	Starter Clutch Bolt	49	5.0	36
	9	Starter Clutch Cover Bolt (L = 40 mm)	9.8	1.0	87	in·lb
	10	Starter Clutch Cover Bolt (L = 20 mm)	9.8	1.0	87	in·lb
	11	Starter Clutch Cover Bolts (L = 30 mm)	9.8	1.0	87	in·lb
	12	Tie-Rod Locknut (Front)	6.9	0.70	61	in·lb	Lh
	13	Tie-Rod Locknut (Rear)	6.9	0.70	61	in·lb

EO: Apply engine oil.

G: Apply grease.

L:Apply a non-permanent locking agent. Lh: Left-hand Threads

M:Apply molybdenum disulfide grease. MO: Apply molybdenum disulfide oil solution.

(mixture of the engine oil and molybdenum disulfide grease in a weight ratio 10:1)

R:Replacement Parts