Road Racing FIM Superbike & Supersport World Championships

2.11.5 The RPM depends upon the mean piston speed corresponding to
the stroke of the engine.
The RPM will be given by the relationship:
N =
30,000 x cm
l
in which: N = prescribed RPM of engine
cm = fixed mean piston speed in m/s
l = stroke in mm
2.11.6 Noise control
Due to the similarity of the piston stroke in different engine configurations within the
capacity classes, the noise test will be conducted at a fixed RPM. For reference
only, the mean piston speed at which the noise test is conducted is calculated at
11 m/sec.
2 cylinders 3 cylinders 4 cylinders
600cc 5,500 RPM 6,500 RPM 7,000 RPM
750cc 5,500 RPM 6,000 RPM 7,000 RPM
over 750cc 5,000 RPM 5,000 RPM 5,500 RPM
2.11.7 The maximum sound level for engines with more than one cylinder
will be measured on each exhaust end.
2.11.8 A motorcycle which does not comply with the maximum sound limits
may be presented several times at pre-race control.
2.11.9 The surrounding sound must not exceed 90 dB/A within a 5 metres
radius from the power source during tests.
2.11.10 Apparatus for noise control must be to international standard IEC
651, Type 1.
The sound level meter must be equipped with a calibrator for control and
adjustment of the meter during periods of use.
2.11.11 The “slow response” setting must always be used.
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