21 TECHNICAL DATA 103
21.1 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 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 (SX‑F EU) 4-gear, claw shifted
Gearbox (All US models) 5-gear, claw shifted
Transmission ratio (SX‑F EU)
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, 75 W
Ignition Contactless controlled fully electronic ignition with digital igni-
tion 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 Electric starter
21.2 Engine tightening torques
Screw, oil jet for piston cooling M4 2 Nm (1.5 lbf ft) Loctite
®
243™
Oil nozzle for clutch lubrication M5 2 Nm (1.5 lbf ft) Loctite
®
243™
Oil nozzle, piston cooling M5 2 Nm (1.5 lbf ft) Loctite
®
243™
Oil nozzle, rocker arm lubrication M5 2 Nm (1.5 lbf ft) Loctite
®
243™
Pulse generator screw and cable
retainer
M5 6 Nm (4.4 lbf ft) Loctite
®
243™
Screw, bearing retainer M5 6 Nm (4.4 lbf ft) Loctite
®
243™
Screw, clutch spring retainer M5 6 Nm (4.4 lbf ft) –
Screw, gear position sensor M5 5 Nm (3.7 lbf ft) Loctite
®
243™
To Next Page
Loading...
Need help?
General
