22 Technical Data; Engine - KTM 350 SX-F 2021 Owner's Manual

22 TECHNICAL DATA

22.1
Design
Displacement
Stroke
Bore
Compression ratio
Idle speed
Control
Valve diameter, intake
Valve diameter, exhaust
Valve clearance
Intake at: 20 °C (68 °F)
Exhaust at: 20 °C (68 °F)
Crankshaft bearing
Conrod bearing
Piston pin bearing
Pistons
Piston rings
Engine lubrication
Primary transmission
Clutch
Gearbox (All SX‑F models)
Gearbox (All XC‑F models)
Transmission ratio (All SX‑F models)
1st gear
2nd gear
3rd gear
4th gear
5th gear
Transmission ratio (All XC‑F models)
1st gear
2nd gear
3rd gear
4th gear
5th gear
6th gear
Alternator
Ignition
Spark plug
Spark plug electrode gap
Cooling
136

Engine

1-cylinder 4-stroke engine, water-cooled
349.7 cm³ (21.34 cu in)
57.5 mm (2.264 in)
88 mm (3.46 in)
14.2:1
2,250 ... 2,350 rpm
DOHC, four valves controlled via cam lever, drive via
timing chain
36.3 mm (1.429 in)
29.1 mm (1.146 in)
0.08 ... 0.15 mm (0.0031 ... 0.0059 in)
0.12 ... 0.19 mm (0.0047 ... 0.0075 in)
2 cylinder bearings
Plain bearing
Bearing bush
Forged light alloy
1 compression ring, 1 oil scraper ring
Pressure circulation lubrication with 2 trochoidal
pumps
24:73
Multidisc clutch in oil bath/hydraulically activated
5 gear transmission, claw shifted
6 gear transmission, claw shifted
14:28
16:26
18:24
21:24
22:21
15:31
16:25
20:25
22:23
25:22
26:20
12 V, 70 W
Contactless controlled fully electronic ignition with
digital ignition adjustment
NGK LMAR9AI-8
0.8 mm (0.031 in)
Water cooling, permanent circulation of coolant by
water pump