KTM 500 EXC - 22 Technical Data; Engine; Engine Tightening Torques; Specifications

22 TECHNICAL DATA 103
22.1 Engine
Design 1-cylinder 4-stroke engine, water-cooled
Displacement 510.4 cm³ (31.147 cu in)
Stroke 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, drive via tooth/wheel
chain
Valve diameter, intake 40 mm (1.57 in)
Valve diameter, exhaust 33 mm (1.3 in)
Valve clearance
Exhaust at: 20 °C (68 °F) 0.12… 0.17 mm (0.0047… 0.0067 in)
Intake at: 20 °C (68 °F) 0.10… 0.15 mm (0.0039… 0.0059 in)
Crankshaft bearing 2 grooved ball bearings
Conrod bearing Needle bearing
Piston pin bearing No bearing bushes - DLC-plated piston pins
Pistons Forged light alloy
Piston rings 1 compression ring, 1 oil scraper ring
Engine lubrication Pressure circulation lubrication with two rotary pumps
Primary transmission 32:76
Clutch Multidisc clutch in oil bath / hydraulically activated
Transmission ratio
1st gear 14:36
2nd gear 17:32
3rd gear 19:28
4th gear 22:26
5th gear 24:23
6th gear 26:21
Alternator 12 V, 200 W
Ignition Contactless controlled fully electronic ignition with digital igni-
tion adjustment, type Kokusan
Spark plug NGK LKAR 8AI - 9
Spark plug electrode gap 0.9 mm (0.035 in)
Cooling Water, permanent circulation of coolant by water pump
Starter Electric starter/kick starter
22.2 Engine tightening torques
Oil jet, piston cooling M4 2 Nm (1.5 lbf ft)
Loctite
®
243™
Screw, cable holder in alternator cover M4 4 Nm (3 lbf ft)
Loctite
®
243™
Oil jet, piston cooling M5 2 Nm (1.5 lbf ft)
Loctite
®
243™
Oil jet, rocker arm lubrication M5 2 Nm (1.5 lbf ft)
Loctite
®
243™
Screw, bearing retainer M5 6 Nm (4.4 lbf ft) Loctite
®
2701
Screw, clutch spring retainer M5 6 Nm (4.4 lbf ft) –
Screw, ignition pulse generator M5 6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, locking lever M5 6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, oil filter cover M5 6 Nm (4.4 lbf ft) –
Screw, oil pump cover M5 6 Nm (4.4 lbf ft)
Loctite
®
243™
Screw, stator M5 6 Nm (4.4 lbf ft)
Loctite
®
243™
Nut, water pump impeller M6 8 Nm (5.9 lbf ft)
Loctite
®
243™
Plug, vacuum connection M6 2.5 Nm (1.84 lbf ft)
Loctite
®
243™