ST4 (2003)

Engine
Type
L-Twin cylinder, 4 valve per cylinder Desmodromic; liquid cooled
Displacement
916cc
Bore x Stroke
94x66mm
Compression Ratio
11:1 
Power
103hp - 76kw @ 9500rpm
Torque
8.6kgm - 84Nm @ 7500rpm
Fuel Injection
Marelli electronic fuel injection, 50mm throttle body
Exhaust
2 aluminum mufflers with 3-way catalytic converter (non-catalytic for USA version)
Trasmission
Gearbox
6 speed
Primary drive
Straight cut gears, ratio 1.84
Ratio
1st 37/15, 2nd 30/17, 3th 27/20, 4th 24/22, 5th 23/24, 6th 24/28
Final drive
Chain; Front sprocket 15; Rear sprocket 43
Clutch
Dry multiplate with hydraulic control
Chassis
Frame
Tubular steel trellis
Front suspension
Showa 43mm upside-down fully adjustable fork
Front Wheel
3-spoke light alloy, 3.50x17
Front Tyre
120/70 ZR17
Rear suspension
Progressive linkage with fully adjustable Sachs monoshock
Rear Wheel
3-spoke light alloy 5.50 x 17
Rear Tyre
180/55 ZR17
wheel-travel-front
130mm / 5.1in
wheel-travel-rear
148mm / 5.8in
Front Brake
2 x 320 mm semi-floating discs, 4-piston caliper
Rear Brake
245mm disc, 2-piston caliper
Instrumentation
Speedometer, rev counter, tripmeter, neutral light, oil pressure warning light, low fuel warning light, high beam indicator, turns signals, LCD display with clock, water temperature, fuel level
Dimensions and Weights
Dry Weight
215kg / 474lb
Seat Height
820mm / 32.8in
Wheelbase
1430mm / 56.3in
Rake
24°
Fuel Tank Capacity
21l (of which 6l reserve) / 5.5 US gal (of which 1.5 US gal reserve)
Number of Seats
Na
Warranty and Maintenance
Warranty
2 years unlimited mileage
Emissions and Consumption
Standard
Emissions are in compliance with Euro1 standard regulations and are also expected to comply with Euro2 regulations, which have still not been defined. (Except for USA version)