Why do we need sound testing ?
Noise is one of the main complaints against motorcycles especially the off road variety.
Noise is cited as the main reason for losing riding areas. In order to protect our access to the areas the T & E MCC uses for hosting our events we must take a proactive stance in managing this issue.
As of 01/07/2013 Sound Testing must be carried out at all permitted events however it is not mandatory to test all machines.
The T & E Club has purchased a Sound Testing Kit and some club members are now qualified M.W.A. Sound Control Officers trained to noise test motorcycles.
Who will be tested
The Clerk of Course will select which bikes are to be tested.
Also any bikes which failed the Sound Emission Test at the last event where they were officially tested.
The Sound Testing procedure
NOTE : The Sound Testing procedure has changed – refer to section 12.10 Sound Emissions section of MOM for the official version. This is an abbreviated version to give everyone a general overview.
The new method is called “2 Metre Max Method”
The selected bike is moved to the centre of the Testing Area with the front of the machine pointing downwind. The measurement is made with the motorcycle uprightand on its wheels with a hot engine.
The Testing Area is basically a 10 metre diameter circle clear of all obstacles with background noise no greater than 100 dB(A).
The Sound Meter is located 2 metres from the rear axle at an angle of 45 degrees and is located on the exhaust side of the bike. The meter is mounted on a stand 1.35 metres above the ground. If the bike has twin exhausts then both sides are tested.
There are only 2 people permitted within the 10 meter diameter circle, the Sound Control Officer ( SCO ) and the rider.
The rider is in control of the bike at all times and is responsible for holding the bike upright.
The rider will be asked the following questions:
- Are you aware of how the test procedure is carried out ?
- Are you aware your engine will be run at full throttle for approx. 1 second ?
- Do you agree to have your machine Sound Tested ?
NOTE : If the rider declines to have their machine tested it is considered a failure and will not be allowed to compete until it has been sound tested and passes. Similar to refusing a RBT.
If the rider agrees to have their bike tested they will be asked to start their machine. The rider will stand on the left hand side of the bike and the SCO on the right. The rider will be asked to pull the clutch in and hold it in during the test. The SCO will open the throttle fully for approx. 1 second. The throttle will then be closed. The SCO will then check the sound meter for a reading.
At all times the rider is responsible for holding the bike upright, the SCO will only operate the throttle during the test.
The rider will be invited to observe the reading if they wish to do so.
This sound emission reading along with the Date, Time and Temperature and other details are recorded in the Recorded Sound Test Log. This log is available to MWA and will be retained in the Club records.
The Noise Limits
The Sound Emission Limit for Enduros is 112 dB(A) with a 4 dB(A) allowance as per General Competition Rules ( GCRs ) 188.8.131.52 Sound Emissions.
I have been Noise Tested now what?
Depending on the reading one of two things will happen …..
If your bike is under the limit then off you go and have a good ride …
If your bike is over the limit then the SCO will fill out a Sound Test Failure Report.
There are 3 copies of this report:
- The rider will receive a copy
- The Clerk of Course will receive another
- The third is a file copy for the Club records.
It is up to the Clerk of Course what action will be taken – not the Sound Control Officer.