KTM 450 SX-F User Manual

22 TECHNICAL DATA 91
22.1 Engine
Design 1-cylinder 4-stroke engine, water-cooled
Displacement 449.3 cm³ (27.418 cu in)
Stroke 63.4 mm (2.496 in)
Bore 95 mm (3.74 in)
Compression ratio 12.6:1
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 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 32:76
Clutch Multidisc clutch in oil bath/hydraulically activated
Gearbox (SX‑F EU) 4-gear, claw shifted
Gearbox (All USA models) 5-gear, claw shifted
Transmission ratio (SX‑F EU)
1st gear 16:32
2nd gear 18:30
3rd gear 20:28
4th gear 22:26
Transmission ratio (All USA models)
1st gear 16:32
2nd gear 18:30
3rd gear 20:28
4th gear 22:26
5th gear 24:24
Alternator 12 V, 75 W
Ignition Contactless controlled fully electronic ignition with digital igni-
tion adjustment
Spark plug NGK LKAR8AI-9
Spark plug electrode gap 0.9 mm (0.035 in)
Cooling Water cooling, permanent circulation of coolant by water pump
Starting aid Electric starter
22.2 Engine tightening torques
Screw, cable holder in alternator cover M4 4 Nm (3 lbf ft) Loctite
®
243™
Screw, oil jet for piston cooling M4 2 Nm (1.5 lbf ft) Loctite
®
243™
Screw, stator M4 4 Nm (3 lbf ft) Loctite
®
648™
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™
Screw, bearing retainer M5 6 Nm (4.4 lbf ft) Loctite
®
2701™
Screw, clutch spring retainer M5 6 Nm (4.4 lbf ft) –
Screw, crankshaft position sensor M5 6 Nm (4.4 lbf ft) Loctite
®
243™
Screw, locking lever M5 6 Nm (4.4 lbf ft) Loctite
®
243™

KTM 450 SX-F Specifications

General

Brand	KTM
Model	450 SX-F
Category	Motorcycle
Language	English