Sound Mesureing

[shercomad125]

At the mintex trial the bikes have to be below 85dBA dose any one now what distance they mesure bike at or what reves they do it at ??

[rabie]

see the sound page of your ACU handbook

off the top of my head, the 85dBA count is at 2m (probably at 45 degrees from the exhaust pipe). trials and enduro uses the "bore and stroke" method (there is a table in your handbook).

so depending upon your bore and stroke you then get the RPM for the sound test.

mx uses a fixed RPM and more recently has moved to other methods - it used to be 50cm~ish away (98, then 96 then 94dBA), also driveby has been done and now the main test involves revving to the rev limiter and taking the sound (but the limit is obviously higher)

[dombush]

although its a good question, pragmatism probably applies here.

Make sure your bike silencer is in good condition . I'm guessing from your username its a Sherco 125 (2008?).

Clearly, these don't have repackable silencers but you should be ok.

I've got a 2007 125 that's well used but well cared for and its as quiet as anything else.

Because trials isn't about power, speed, fashion, sustained high revs etc. very few people on modern 2T's meddle with silencers.

Therefore I suspect that the sound testing will constitute looking for non standard / damaged silencers and then some testing based on "here, Bert..that sounds noisy!!"

Happy to hear I'm wrong but I'd be surprised.

[shercomad125]

Yer I have a 08

[rabie]

in addition to sound testing the "Clerk of the Course" has the power to exclude the rider if they (CofC) deam the rider's bike to be "excessivly noisey", a usefull little rule if you haven't a sound meter or something else goes wrong.