22 TECHNICAL DATA
136
22.1 Engine
Design 1-cylinder 4-stroke engine, water-cooled
Displacement 349.7 cm³ (21.34 cu in)
Stroke 57.5 mm (2.264 in)
Bore 88 mm (3.46 in)
Compression ratio 14.2:1
Idle speed 2,250 … 2,350 rpm
Control DOHC, four valves controlled via cam lever, drive via
timing chain
Valve diameter, intake 36.3 mm (1.429 in)
Valve diameter, exhaust 29.1 mm (1.146 in)
Valve clearance
Intake at: 20 °C (68 °F) 0.08 … 0.15 mm (0.0031 … 0.0059 in)
Exhaust at: 20 °C (68 °F) 0.12 … 0.19 mm (0.0047 … 0.0075 in)
Crankshaft bearing 2 cylinder bearings
Conrod bearing Plain 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 2 trochoidal
pumps
Primary transmission 24:73
Clutch Multidisc clutch in oil bath/hydraulically activated
Gearbox (All SX‑F models) 5 gear transmission, claw shifted
Gearbox (All XC‑F models) 6 gear transmission, claw shifted
Transmission ratio (All SX‑F models)
1st gear 14:28
2nd gear 16:26
3rd gear 18:24
4th gear 21:24
5th gear 22:21
Transmission ratio (All XC‑F models)
1st gear 15:31
2nd gear 16:25
3rd gear 20:25
4th gear 22:23
5th gear 25:22
6th gear 26:20
Alternator 12 V, 70 W
Ignition Contactless controlled fully electronic ignition with
digital ignition adjustment
Spark plug NGK LMAR9AI-8
Spark plug electrode gap 0.8 mm (0.031 in)
Cooling Water cooling, permanent circulation of coolant by
water pump