23 TECHNICAL DATA
143
23.1
Engine
Design
1-cylinder 4-stroke engine, water-cooled
Displacement (FE 450 US)
449.9 cm³ (27.455 cu in)
Displacement (FE 501 US)
510.9 cm³ (31.177 cu in)
Stroke (FE 450 US)
63.4 mm (2.496 in)
Stroke (FE 501 US)
72 mm (2.83 in)
Bore
95 mm (3.74 in)
Compression ratio
11.8:1
Idle speed
1,800 … 1,900 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 grooved ball bearings
Conrod bearing
Slide bearing
Piston pin bearing
Not a bearing bush - DLC-plated piston pins
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
6-gear, claw shifted
Transmission ratio
First gear
14:36
Second gear
17:32
Third gear
19:28
Fourth gear
22:26
Fifth gear
23:24
Sixth gear
26:21
Alternator
12 V, 168 W
Ignition
Contactless controlled fully electronic ignition with
digital ignition adjustment
Spark plug
NGK LKAR9AI-10
Spark plug electrode gap
1.0 mm (0.039 in)
Cooling
Water cooling, permanent circulation of coolant by
water pump
Starting aid
Electric starter