There are different limits in place for different vehicle classes.

The usual 'car' on the road falls into a lower noise limit than trucks or motorcycles. Can have a noisy as Harley in a suburb, but not a noisy car.

You'll find most of it relates back to 1970's rules and regulations and hasn't been updated properly since.

A thing to note: (If I remember my sound stuff) 100db is twice as loud as 90db... It's on a logarithmic scale.

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]

I think you do recall correctly

10dB increase = 10x the sound intensity = approximately 2x as loud (this is perceived loudness and it depends on the ear's sensitivity to that particular frequency)

3dB increase = 2x the sound intensity but not 2x the perceived loudness.

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MY99 WRX (Sold)
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Well, assuming that the biggest truck allowed in a built up neighbourhood makes..say 103db..then logically (assuming laws makers know what that is) wouldnt that be the allowed limit for ANY vehicle?...whats the point in having diffrent noise limits for diffrent vehicles...that would be implying that the human ear has some kind of inbuilt devise that diffrentiates what it classifies as "noise" or "loud"...ie a rex driving by is noise at 91db, a truck driving at 103db by is "OK" (just becouse the law states that it is?)....i dont know man..still doesnt make sense..I guess common sense wasnt standard issue back in 1970...lol

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Aint no stupid like right-wing stupid.....

Has anyone considered that a trucks 103db is not just exhaust noise it's the vehicles total noise output.

Trucks have Pneumatics that create noise in their normal operation i.e. air spring brakes, exhaust brakes, Air shifted gearboxes etc.

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Trucks maximum may be 103db (or whatever it is), but I don't see too many semi trailers running through my suburbs streets. As they are on highways for 90% of the time, the extra noise is not that much of an issue.

Also as rossco said, the pneumatics would create a lot of 'noise' rather than outright engine noise.

Plus who cares anyway? They aren't going to up the car noise level to 100db, so forget about the other regulations...

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]

I just don't get how Harley's get away with their noise levels. Never seen one pulled over by the cops.

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Subaruless

They will only lower it in future ADR's like they always have.

I think Europe is down to 80dba for 2010 produced passanger vehicles.

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I have asked that question myself ..... was told by a harley enthusiast that they get away with it like this (dont know if its true or a story but its what he span me)

Harleys produced before 1968 (i think he said 68) can get away with the noise levels so they just register their harley as a 68 model. He said there are significantly more 68 harleys registered in Australia than were ever produced. But its how they get around the law.

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Foxy

Not speeding Officer........Qualifying.

Haha, I just figure that they're all part of Coffin Cheaters/Bandido's/name that gang, running illicit substance and obscene amounts of money around the place, and offering the fuzz kickbacks to let them seamlessly conduct their 'business'...

And the po-po probably thinking they will shot in the face roadside if they were to pull them over... lol.

Brent.

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My point exactly...Harleys are even louder than some trucks...i think this is another law that was not well thought out...

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Aint no stupid like right-wing stupid.....