Ducati ST4

Make Model	Ducat ST4
Year	1997 - 98
Engine	Four stroke, 90° “L” twin cylinder, DOHC, desmodromic 4 valves per cylinder
Capacity	916 cc / 55.9 cu in
Bore x Stroke	94 x 66 mm
Cooling System	Liquid cooled
Compression Ratio	11.0:1
Lubrication	Wet sump
Engine Oil	Synthetic, 20W/50
Exhaust	2 aluminum mufflers with catalytic converter (non-catalytic on USA version)
Induction	Fuel injection, 50 mm throttle body, Marelli 1.6M
Ignition	Marelli electronic
Spark Plug	Champion, RA59GC
Starting	Electric
Battery	12V 16Ah
Max Power	78.7 kW / 107 hp @ 9000 rpm
Max Torque	89 Nm / 9 kgf-m / 65.6 ft-lb @ 7500 rpm
Clutch	Hydraulically actuated dry multiplate clutch
Transmission	6 Speed
Primary Drive Ratio	1.84:1 (32/59)
Gear Ratios	1st 2.466 / 2nd 1.765 / 3rd 1.350 / 4th 1.091 / 5th 0.958 / 6th 0.857:1
Final Drive Ratio	2.53:1 (15/38)
Final Drive	Chain
Frame	Steel, Trellis frame
Front Suspension	Showa GD081 43mm upside-down fully adjustable fork.
Front Wheel Travel	130 mm / 5.1 in
Rear Suspension	Progressive linkage with fully adjustable Showa GD082 monoshock with piggy back aluminum swing arm.
Rear Wheel Travel	148 mm / 5.8 in
Front Brakes	2x 320 mm Discs, 4 piston calipers
Rear Brakes	Single 245 mm disc, 2 piston caliper
Front Tyre	120/70 - ZR17
Rear Tyre	180/55 - ZR17
Dimensions	Length: 2070 mm / 81.5 in Width: 910 mm / 35.8 in Height: 1180 mm / 46.5 in
Wheelbase	1430 mm / 56.3 in
Seat Height	820 mm / 32.3 in
Dry Weight	214.5 kg / 474 lbs
Fuel Capacity	21 Litres / 5.5 US gal / 4.6 Imp gal
Consumption Average	5.1 L/100 km / 19.8 km/l / 46.6 US mpg / 55.9 Imp mpg
Standing ¼ Mile	11.3 sec / 200 km/h / 124 mph
Top Speed	251 km/h / 156 mph

Ducati had launched its first sports touring machine, the ST2, in 1996, and although it was a success in many markets, it was also criticized for its lack of top-end power. So for 1998, Ducati expanded its sports touring range with a new ST4, while keeping the ST2 in production as a cheaper option.

The ST4 was basically an ST2 chassis and bodywork with a 916cc eight-valve desmodromic engine fitted. That engine installation was straightforward, although the front cylinder head was modified from the standard 916 Biposto design in order to fit the motor into the ST2 frame. The exhaust camshaft was moved down in the head by 10mm (0.3in), allowing the larger engine to fit.

The same steel-tube trellis frame, Showa upside-down front forks and Showa rear shock as the ST2 give the ST4 firm handling, although the more powerful engine places heavier stresses upon it.

For 2000, the ST4 was modified with several uprated parts. A wider rear wheel took a larger 180-section tyre, and the brakes and dash were uprated over the ST2 parts. A new sidestand design replaced the previous flip-up design and there were some detail engine changes, mostly to improve reliability.

On the road, the ST4 makes a capable sports tourer, although it is not as effective as Honda's VFR800. The engine is very strong, allowing all-day high-speed cruising,

and the 21-litre (4.6 gal) fuel tank gives a decent 320km (200 mile) range. Sporty handling makes short work of twisty back roads, while the strong Brembo brakes and sharp steering are even useful on the track.