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Specifications

Note: Where applicable, models are identified by their production code letter - refer to 'Identification numbers' at the front of this manual for details.

General

Type Four-stroke, dohc, in-line twin cylinder

Capacity 499 cc

Bore 73 mm

Stroke 59.6 mm

Compression ratio 10.5 to 1

Cylinder numbering 1-2 from left to right

Cooling system Liquid cooled

Clutch Wet multi-plate

Transmission Six-speed constant mesh

Final drive Chain

Cylinder head

Warpage (max) ..

0.10 mm

2»2 Engine, clutch and transmission

Camshafts

Inlet lobe height

Standard 36.280 to 36.360 mm

Service limit (min) 36.250 mm

Exhaust lobe height

Standard 36.370 to 36.450 mm

Service limit (min) 36.340 mm

Journal diameter

Standard 24.949 to 24.970 mm

Service limit (min) 24.940 mm

Journal oil clearance

Standard 0.030 to 0.072 mm

Service limit (min) 0.100 mm

Runout (max) 0.05 mm

Valves, guides and springs

Valve clearances see Chapter 1

Inlet valve

Stem diameter

Standard 4.475 to 4.490 mm

Service limit (min) 4.465 mm

Guide bore diameter

Standard 4.500 to 4.412 mm

Service limit (max) 4.562 mm

Stem-to-guide clearance

Standard 0.010 to 0.037 mm

Service limit (max) Not available

Seat width

Standard 1.0 mm

Service limit 1.5 mm

Valve guide height above cylinder head 15.30 to 15.50 mm

Exhaust valve

Stem diameter

Standard 4.465 to 4.480 mm

Service limit (min) 4.455 mm

Guide bore diameter

Standard 4.500 to 4.512 mm

Service limit (max) 4.612 mm

Stem-to-guide clearance

Standard 0.020 to 0.047 mm

Service limit (max) Not available

Seat width

Standard 1.0 mm

Service limit 1.5 mm

Valve guide height above cylinder head 15.30 to 15.50 mm

Valve springs free length (inlet and exhaust)

Standard 37.86 mm

Service limit (min) 36.1 mm

Clutch

No. of friction plates 7

No. of plain plates 6

Friction plate thickness

Standard 2.92 to 3.08 mm

Service limit (min) 2.60 mm

Plain plate warpage (max) 0.3 mm

Spring free height

Standard 43.2 mm

Service limit (min) 42.0 mm

Clutch housing sleeve outside diameter

Standard 29.993 to 30.007 mm

Service limit (min) 29.96 mm

Clutch housing sleeve inside diameter

Standard 21.980 to 21.993 mm

Service limit (max) 22.03 mm

Transmission input shaft outside diameter at sleeve point

Standard 21.967 to 21.980 mm

Service limit (max) 21.950 mm

Engine, clutch and transmission 2«3

Lubrication system

Oil pressure see Chapter 1

Oil pump Inner rotor tip-to-outer rotor clearance

Standard 0.15 mm

Service limit (max) not available

Outer rotor-to-body clearance

Standard 0.15 to 0.21 mm

Service limit (max) not available

Rotor end-float

Standard 0.02 to 0.09 mm

Service limit (max) not available

Cylinder bores

Bore

Standard 73.000 to 73.015 mm

Service limit (max) 73.10 mm

Warpage (max) 0.10 mm

Ovality (out-of-round) (max) 0.10 mm

Taper (max) 0.10 mm

Cylinder compression see Chapter 1

Connecting rods

Small-end inside diameter

Standard 17.016 to 17.034 mm

Service limit (max) 17.07 mm

Small-end-to-piston pin clearance

Standard 0.016 to 0.040 mm

Service limit (max) Not available

Big-end side clearance

Standard 0.06 to 0.10 mm

Service limit (max) 0.30 mm

Big-end oil clearance

Standard 0.030 to 0.052 mm

Service limit (max) 0.06 mm

Pistons

Piston diameter (measured at 90° to piston pin axis)

Standard 72.970 to 72.990 mm

Service limit (min) 72.90 mm

Piston-to-bore clearance

Standard 0.010 to 0.045 mm

Service limit (max) Not available

Piston pin diameter

Standard 16.994 to 17.000 mm

Service limit (min) 16.98 mm

Piston pin bore diameter in piston

Standard 17.002 to 17.008 mm 2

Service limit (max) 17.02 mm

Piston pin-to-piston pin bore clearance

Standard 0.002 to 0.014 mm

Service limit (max) Not available

Piston rings

Ring end gap (installed) Top ring

Standard 0.15 to 0.30 mm

Service limit (max) 0.50 mm

2nd ring

Standard 0.30 to 0.45 mm

Service limit (max) 0.60 mm

Oil ring side-rail

Standard 0.20 to 0.70 mm

Service limit (max) 1.00 mm

Ring-to-groove clearance Top ring

Standard 0.025 to 0.060 mm

Service limit (max) 0.08 mm

2nd ring

Standard 0.015 to 0.050 mm

Service limit (max) 0.08 mm

2»4 Engine, clutch and transmission

Crankshaft and bearings

Main bearing oil clearance

Standard 0.026 to 0.044 mm

Service limit (max) 0.05 mm

Runout (max) 0.05 mm

Transmission

Gear ratios (No. of teeth)

Primary reduction 1.947 to 1 (74/38T)

1st gear 3.461 to 1 (45/13T)

2nd gear 2.235 to 1 (38/177)

3rd gear 1.750 to 1 (35/20T)

4th gear 1.478 to 1 (34/23T)

5th gear 1.280 to 1 (32/25T)

6th gear 1.130 to 1 (26/23T)

Final reduction 2.666 to 1 (40/15T)

Input shaft 5th and 6th gears inside diameter

Standard 28.000 to 28.021 mm

Service limit (max) 28.04 mm

Input shaft 5th and 6th gears, bush outside diameter

Standard 27.959 to 27.980 mm

Service limit (min) 27.94 mm

Input shaft 5th and 6th gears gear-to-bush clearance

Standard 0.020 to 0.062 mm

Service limit (max) not available

Input shaft 5th gear bush inside diameter

Standard 24.985 to 25.006 mm

Service limit (max) 25.016 mm

Input shaft outside diameter at 5th gear bush point

Standard 24.967 to 24.980 mm

Service limit (min) 24.960 mm

Input shaft-to-bush clearance at 5th gear bush point

Standard 0.005 to 0.039 mm

Service limit (max) not available

Output shaft 1st gear inside diameter

Standard 24.000 to 24.021 mm

Service limit (max) 24.04 mm

Output shaft 2nd, 3rd and 4th gears inside diameter

Standard 31.000 to 31.021 mm

Service limit (max) 31.04 mm

Output shaft 2nd gear bush outside diameter

Standard 30.955 to 30.980 mm

Service limit (min) 30.94 mm

Output shaft 3rd and 4th gears bush outside diameter

Standard 30.950 to 30.975 mm

Service limit (min) 30.93 mm

Output shaft 2nd gear, gear-to-bush clearance

Standard 0.020 to 0.070 mm

Service limit (max) not available

Output shaft 2nd gear bush inside diameter

Standard 27.985 to 28.006 mm

Service limit (max) 28.021 mm

Output shaft outside diameter at 2nd gear bush point

Standard 27.967 to 27.980 mm

Service limit (min) 27.960 mm

Output shaft-to-bush clearance at 2nd gear bush point

Standard 0.005 to 0.039 mm

Service limit (max) not available

Selector drum and forks

Selector fork end thickness

Standard 5.93 to 6.00 mm

Service limit (min) 5.90 mm

Selector fork bore inside diameter

Standard 12.000 to 12.021 mm

Service limit (max) 12.03 mm

Selector fork shaft outside diameter

Standard 11.969 to 11.980 mm

Service limit (min) 11.96 mm

Engine, clutch and transmission 2*5

Torque settings

Engine mountings

Mounting bolts

Sub frame bolts and nuts

Valve cover bolts

Camchain tensioner bolts

Camshaft holder bolts

Timing inspection plug

Centre plug (in alternator cover)

9 mm cylinder head bolts

6 mm cylinder head bolts

Alternator rotor bolt

Primary drive gear bolt

Balancer gear nut

Clutch centre nut

Clutch release plate bolts

Oil pump sprocket bolt

Oil pump assembly bolt

Gearchange lever pinch bolt

Neutral switch

Oil pressure switch

Selector cam bolt

Gearchange mechanism return spring locating

Crankcase 10 mm bolts

Crankcase 8 mm bolts

Crankcase 6 mm bolts

Connecting rod big-end cap nuts

45 Nm

45 Nm

10 Nm

10 Nm

12 Nm

10 Nm

7 Nm

48 Nm

12 Nm

95 Nm

95 Nm

85 Nm

85 Nm

12 Nm

15 Nm

8 Nm

23 Nm

12 Nm

12 Nm

23 Nm

In 23 Nm

40 Nm

25 Nm

12 Nm

34 Nm