22 TECHNICAL DATA
138
22.1
Engine
Design
1-cylinder 4-stroke engine, water-cooled
Displacement
449.9 cm³ (27.455 cu in)
Stroke
63.4 mm (2.496 in)
Bore
95 mm (3.74 in)
Compression ratio
12.75:1
Idle speed
2,250 … 2,350 rpm
Control
OHC, 4 valves controlled via rocker arm
Valve diameter, intake
40 mm (1.57 in)
Valve diameter, exhaust
33 mm (1.3 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)
0.12 … 0.17 mm (0.0047 … 0.0067 in)
Crankshaft bearing
2 cylinder roller bearing
Conrod bearing
Slide bearing
Piston pin bearing (All SX
‑
F standard models,
XC
‑
F US)
No bearing bush
–
DLC coated piston pin
Piston pin bearing (HERLINGS REPLICA,
FACTORY EDITION)
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
31:76
Clutch
Multidisc clutch in oil bath, hydraulically activated
Gearbox (SX
‑
F EU, HERLINGS REPLICA)
4 gear transmission, claw shifted
Gearbox (All US models)
5 gear transmission, claw shifted
Transmission ratio (SX
‑
F EU, HERLINGS REPLICA)
First gear
16:32
Second gear
18:30
Third gear
20:28
Fourth gear
22:26
Transmission ratio (All US models)
First gear
16:32
Second gear
18:30
Third gear
20:28
Fourth gear
22:26
Fifth gear
24:24
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
Starting aid
Starter motor
Summary of Contents for 450 SX-F 2019
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