KTM 250 SX-F 2005, Repair Manual

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Repair manual KTM 250 SX-F
Art.-No. 3.206.027-E
TECHNICAL DATA – ENGINE 250 SX-F
Design Liquid-cooled single cylinder 4-stroke engine
Displacement 249.51 ccm
Bore/Stroke 76 / 55 mm
Ratio 12.8 : 1
Fuel unleaded fuel with at least RON 95
Valve timing 4 valves controlled by finger levers and 2 camshafts,
driven by a pair of spur gears and a tooth-type chain
Camshaft 05
Valve diameter Intake 30.9 mm
Valve diameter Exhaust 26.5 mm
Valve clearence cold Intake 0.10 - 0.20 mm
Valve clearence cold Exhaust 0.12 - 0.22 mm
Crank shaft bearing
2 cylinder roller bearings
Connecting rod bearing needle bearing
Top end bearing bronze bushing
Piston alluminium alloy forged
Piston rings 1 compression ring, 1 oil scraper ring
Engine lubrication pressure circulation lubrication with 2 rotor pumps
Engine oil full synthetic oil (Motorex Power Synt 4T 10W/50)
Quantity of engine oil 1.1 liters
Primary drive 22:68
Transmission claw shifted 6-speed
1st gear 13:32
2nd gear 15:30
3rd gear 17:28
4th gear 19:26
5th gear 21:25
6th gear 22:24
Ignition system contactless DC-CDI ignition with digital advanced system by KOKUSAN
Generator no generator
Spark plug NGK CR 9 EBK
Cooling system liquid cooled, permanent rotation of cooling liquid through mechanically driven water pump
Cooling liquid 1.2 liters, 50% antifreeze, 50% destilled water, at least -25° (-13° F)
BASIC CARBURATOR SETTING
250 SX-F
Type Keihin FCR-MX 3925D
Main jet 168
Jet needle OBETP
Idling jet 40
Main air jet 200
Idling air jet 100
Needle position 5 th from top
Starting jet 85
Mixture control screw open 1.25
Slide 15
Performance restrictor –
Stop pump membrane 858 / 2.15 mm
Hot start device 2.5 mm