Repair manual KTM 250 / 300 / 380 Art No 3206004 -E
9-21C
Engine 250 SX 250 EXC 300 EXC 380 SX 380 EXC
Design Liquid-cooled single-cylinder two-stroke engine with KTM Twin Valve Control exhaust system and KTM Torque Chamber
Piston displacement 249 ccm 297 ccm 368 ccm
Bore / stroke 66.4 / 72 mm (2.62 / 2.84 in) 72 / 73 mm (2.84 / 2.88 in) 78 / 77 mm (3 / 2.98 in)
Fuel unleaded SUPER fuel, research octane no 95, mixed with high-grade two stroke oil (Shell Advance Racing X)
Oil / gasoline ratio 1:40 – 1:60 when using high grade two stroke oil. When in doupt, please contact your importer or use 1:40 mix ratio to be on the safe side
Crankshaft bearing 1 deep-groove ball bearing / 1 cylinder roller bearing
Connecting rod bearing needle bearing
Piston pin bearing needle bearing
Piston cast piston forged piston cast piston
Piston ring one plain compression ring two plain compression rings
Dimension "X"
0 + 0.1 mm (0 + 0.004 in)
Ignition timing 1,9 mm (0,07 in) BTDC 2.4 mm (0.095 in) BTDC 2.43 mm (0.096 in) BTDC 2.6 mm (0.1 in) 17 °) BTDC
Spark plug NGK BR 8 ECM
Electrode gap 0.6 mm (0.024 in)
Dimension "Z"
49,5 mm (1.94 in) 46 mm (1.7 in) 50.5 mm (1.99 in)
TVC start open 5000/min 5900/min 5200/min
TVC fully open 7000/min 7750/min 7200/min
Primary drive straight cut spur gears, primary ratio 25:72 straight cut spur gears, primary ratio 26:72
Clutch multiple disc clutch in oil bath, hydraulic operated (Shell HF-E15)
Transmission 5 speed, claw actuated
Gear ratio
1
st
Gear 15:29 15:29 15:29 15:29
2
nd
Gear 17:27 18:26 18:26 18:26
3
rd
Gear 19.25 19:22 19:24 19:22
4
th
Gear 21:23 21:20 21:23 21:20
5
th
Gear 23:21 23:18 23:21 23:18
Gear lubrication
0,8 l engine oil 20W-40 (Shell Advance VSX4)
0,8 l gear oil 80W (Shell Gear EP 80)
0,8 l engine oil 20W-40 (Shell Advance VSX4)
0,8 l gear oil 80W (Shell Gear EP 80)
ailable chain sprockets 13t / 14t / 15t for chain
5
/
8 x
1
/
4"
Coolant 1.3 litres, 40% anti freeze, 60% water, at least -25 °C (-13 °F)
Ignition system KOKUSAN 2K-4 KOKUSAN 2K-3 KOKUSAN 2K-3 KOKUSAN 2K-3
Generator output no generator 12V 110W no generator 12V 110W
Carburetor flat-slide carburetor, carburetor setting see table
Air-filter wet foam type air filter insert
(upper edge piston -
upper edge cylinder)
(height of the
control flap)
TECHNICAL DATA - ENGINE 250/300/380 SX / EXC 2001 (all models out of USA)
