25 Technical Data; Engine - Husqvarna FC 450 2018 Repair Manual

25 TECHNICAL DATA

25.1
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
Transmission ratio
First gear
Second gear
Third gear
Fourth gear
Fifth gear
Alternator
Ignition
Spark plug
Spark plug electrode gap
Cooling
Starting aid
280

Engine

1-cylinder 4-stroke engine, water-cooled
449.9 cm 3 (27.455 cu in)
63.4 mm (2.496 in)
95 mm (3.74 in)
12.75:1
2,250 ... 2,350 rpm
OHC, 4 valves controlled via rocker arm
40 mm (1.57 in)
33 mm (1.3 in)
0.10 ... 0.15 mm (0.0039 ... 0.0059 in)
0.12 ... 0.17 mm (0.0047 ... 0.0067 in)
2 cylinder roller bearing
Slide bearing
No bearing bush - DLC coated piston pin
Forged light alloy
1 compression ring, 1 oil scraper ring
Pressure circulation lubrication with two Eaton
pumps
31:76
Multidisc clutch in oil bath, hydraulically activated
5 gear transmission, claw shifted
16:32
18:30
20:28
22:26
24:24
12V, 70W
Contactless controlled fully electronic ignition with
digital ignition adjustment
NGK LMAR9Al-8
0.8 mm (0.031 in)
Water cooling, permanent circulation of coolant by
water pump
Starter motor