Breakthrough in Motocross noise?

" average reduction between 3 and 6 dB/A, compared to the current situation..."
Breakthrough in Motocross noise?

The noise emitted by off-road machines, which has increased dramatically in the four-stroke era - prompting a backlash from the public and resulting in the loss of many off-road facilities - could finally be nearing a solution.

Like an alcoholic told by doctors about the damage drink is doing to him, but who keeps going to the bar, the manufacturers have produced machines with unnecessary levels of noise - especially for amateur racing - year after year. But since these motorcycles have been built to rules set by the main racing organisations, led by the FIM, blame is shared by all parties.

Decibel limits have steadily been reduced, but with the old method of noise measurement producing inconsistent 'real world' results - and widely open to abuse - little progress has been made on the biggest issue (along with rising machine costs) facing modern off-road motorcycling.

Two years ago, unable to ignore the growing call for action on the subject, the FIM announced an initiative to reduce the sound levels of off-road motorcycles.

With the support of manufacturers and promoters, a new sound test method called "2 metre max" was devised and extensively tested.

This new sound test is carried out with a sound meter positioned at the rear of the motorcycle, at a distance of two metres and an angle of 45? from the silencer. The engine is tested at maximum rpm.

In what is being labelled as a turning point in the war against destructive noise, the "2 metre max" rule will now come into effect for the 2010 FIM Motocross, Enduro and Track Racing World Championships.

The FIM states that the 'noise levels permitted will be an important first step in the reduction of sound levels, with an average reduction between 3 and 6 dB/A, compared to the current situation, depending on the discipline.'

For Motocross and Track Racing, the maximum noise level admitted at a distance of 100 metres will be of 81 dB/A, and in Enduro the maximum noise level admitted at a distance of 100 metres will be 78 dB/A.

"A major step has been made with the implementation of this new method, thanks to an excellent cooperation between manufacturers and promoters, not to mention the strong impulse given by the Danish federation," said Jean-Pierre Mougin, FIM deputy president and chairman of the Committee for the reduction of sound levels.

"This is important for the survival of all FIM off-road disciplines. The FIM had to react effectively. 2010 will constitute a first step in the fight against noise nuisances and the results will define the future actions."

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