20
TECHNICAL DATA
91
20.1
Engine
Design
1-cylinder 4-stroke engine, water-cooled
Displacement
449.3 cm³ (27.418 cu in)
Stroke
60.8 mm (2.394 in)
Bore
97 mm (3.82 in)
Compression ratio
12.5:1
Idle speed
1,550… 1,650 rpm
Control
DOHC, four valves controlled via cam lever, drive via helical gear
pair and tooth-wheel chain
Valve diameter, intake
40.4 mm (1.591 in)
Valve diameter, exhaust
31.7 mm (1.248 in)
Valve clearance, cold, intake
0.10… 0.15 mm (0.0039… 0.0059 in)
Valve clearance, cold, exhaust
0.15… 0.20 mm (0.0059… 0.0079 in)
Crankshaft bearing
2 cylinder roller bearing
Conrod bearing
Needle bearing
Piston pin bearing
No bearing bush - piston pin made of TiAl alloy with DLC coat-
ing
Pistons
Forged light alloy
Engine lubrication
Pressure circulation lubrication with 3 rotor pumps
Primary transmission
29:74
Clutch
Multidisc clutch in oil bath/hydraulically activated
Transmission ratio
1st gear
14:35
2nd gear
17:33
3rd gear
19:30
4th gear
21:28
5th gear
23:26
Alternator
12 V, 200 W
Ignition
Contactless controlled fully electronic ignition with digital igni-
tion adjustment
Spark plug
NGK CR 9 EKB
Spark plug electrode gap
0.7 mm (0.028 in)
Cooling
Water cooling, permanent circulation of coolant by water pump
Starting aid
Electric starter
20.2
Engine tightening torques
Jet, engine case breather
M4
On block
Loctite
®
243™
Oil jet, cam lever lubrication
M4
6 Nm (4.4 lbf ft)
Loctite
®
243™
Oil jet, piston cooling
M4
4 Nm (3 lbf ft)
Loctite
®
243™
Locking screw for bearing
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Oil jet, clutch oil supply
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, bearing bolt of oil pump idler
shaft
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, camshaft bearing retaining
bracket
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, ignition pulse generator
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, ignition pulse generator adapter M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, locking lever
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, oil filter cover
M5
6 Nm (4.4 lbf ft)
–
Screw, oil pump cover
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, stator bracket
M5
6 Nm (4.4 lbf ft)
Loctite
®
243™