Engine
Twin cylinder, four-stroke, 90° "L" type, longitudinal.
Bore mm:
90 (749/749S/749Dark).
Stroke mm:
58.8 (749/749S/749Dark).
Total displacement cm
E
748 (749/749S/749Dark).
Compression ratio:
11,7±0,5:1 (749/749Dark);
12,3±0,5:1(749S).
Max power at crankshaft (95/1/EC), kW/HP:
76/103 at 10,000 rpm (749/749Dark);
81/110 at 10,500 rpm (749S);
Max torque at crankshaft (95/1/EC):
77 Nm at 8,500 rpm (749/749Dark);
78 Nm at 8,500 rpm (749S);
Max rotation speed, rpm.
11.200
Important
Do not exceed specified rpm limits in any running
condition.
Timing system
Desmodromic (type) with four valves per cylinder, operated
by eight rocker arms (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.
86
3
:
Desmodromic timing system (fig. 82)
1) Opening (or upper) rocker;
2) opening rocker shim;
3) closing (or lower) rocker shim;
4) return spring for lower rocker;
5) closing (or lower) rocker;
6) camshaft;
7) valve.
6
1
2
3
7
5
4
fig. 82