TM RACING 250 EN, Workshop Manual

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3
TECHNICAL SPECIFICATIONS
ENGINE TECHNICAL DATA 250-300 mx smx
ENGINE 250 300
Type Single cylinder 2-stroke, liquid-cooled
Displacement 249,3 cm
3
293,1 cm
3
Bore/stroke 66.4x72 72x72
Compression 14.5:1 11.5:1
Fuel (E5) / (E10) super unleaded fuel mixed with oil at 3%
Squish height 1.6 / 1.7 mm
Piston height from the cylinder surface to the PMS 0.75 ÷ 0.80 mm
PIston cylinder tolerance 0,06 / 0,07
Engine shaft supports 2 roller bearings
Small-end bearing silvery needle roller cage
Big-end bearing needle roller cage
Piston forged in light alloy
Segments 2 segments (GAP 0,60 / 0,65)
Gearbox oil quantity 700 cc
Primary transmission straight-toothed gears 19/57
Clutch multiple disc oil bath
Gearbox (with front couplings) 5 gears
Gear ratios
1
a
15:27
2
a
17:25
3
a
19:23
4
a
21:21
5
a
23:20
Ignition CDI EMOTICOM
Generator 12V 180W
Regulator KOKUSAN
Spark plug NGK BKR 8EIX
Electrodes distance 0,7-0,75 mm
Cooling fluid, 40% antifreeze, 60% water (up to -25°C),
circulation forced with pump
Fluid amount 1 liter (see page 4-97)