Ducati ST4S - Engine Specifications

77
E
7
6
6
8
2
1
5
1
3
4
Engine
Twin cylinder, four-stroke, 90° “L” type, longitudinal.
Bore:
98 mm
Stroke:
66 mm
Total displacement:
996 c.c.
Compression ratio:
11.5±0.5:1
Max. power at crankshaft (95/1/EC):
86 kW – 117 HP at 8750 rpm
Max torque at crankshaft (95/1/EC):
10 kgm at 7000 rpm
Max. rotation speed
10,000 rpm
Important
Do not exceed specified rotation speed limits under
any running condition.
Timing system
Desmodromic (type) with four valves per cylinder,
operated by eight rockers (4 opening rockers and 4
closing rockers) and two overhead camshafts. It is
operated by the crankshaft through spur gears, belt
rollers and toothed belts.
fig. 80
Desmodromic timing system (fig. 80)
1) Opening (or upper) rocker.
2) Opening rocker shim.
3) Split rings.
4) Closing (or lower) rocker shim.
5) Return spring for lower rocker.
6) Closing (or lower) rocker.
7) Camshaft.
8) Valve.