25 TECHNICAL DATA
25.1
Engine
Design
1-cylinder 4-stroke engine, water-cooled
Displacement
249.91 cm
3
(15.2505 cu in)
Stroke
52.3 mm (2.059 in)
Bore
78 mm (3.07 in)
Compression ratio
14.4:1
Idle speed
2,250 ... 2,350 rpm
Control
DOHC, four valves controlled via cam lever, drive via
timing chain
Valve diameter, intake
32.5 mm (1.28 in)
Valve diameter, exhaust
26.5 mm (1.043 in)
Valve clearance
Intake at: 20 °C (68 °F)
0.10 ... 0.15 mm (0.0039 ... 0.0059 in)
Exhaust at: 20 °c (68 °F)
0.13 ... 0.18 mm (0.0051 ... 0.0071 in)
Crankshaft bearing
2 cylinder bearings
Conrod bearing
Slide bearing
Piston pin bearing
Bearing bush
Pistons
Forged light alloy
Piston rings
1 compression ring, 1 oil scraper ring
Engine lubrication
Pressure circulation lubrication with two Eaton
pumps
Primary transmission
24:73
Clutch
Multidisc clutch in oil bath/hydraulically activated
Gearbox
5 gear transmission, claw shifted
Transmission ratio
1st gear
13:32
2nd gear
16:32
3rd gear
17:28
4th gear
19:26
5th gear
21:25
Alternator
12V, 70W
Ignition
Contactless controlled fully electronic ignition with
digital ignition adjustment
Spark plug
NGK LMAR9Al-8
Spark plug electrode gap
0.8 mm (0.031 in)
Cooling
Water cooling, permanent circulation of coolant by
water pump
Starting aid
Starter motor
268