Sound level test created by SAE

[RandyR]

July 8, 2009 - The Society of Automotive Engineers (SAE) International has produced a simple, consistent and economical sound test standard that can be used to determine whether a street bike (on-highway motorcycle) exhaust system emits excessive sound, the American Motorcyclist Association (AMA) reports.

The J2825 "Measurement of Exhaust Sound Pressure Levels of Stationary On-Highway Motorcycles," issued by the SAE in May, establishes instrumentation, test site, test conditions, procedures, measurements and sound level limits. According to the SAE, the J2825 standard is based on a comprehensive study of a wide variety of on-highway motorcycles.

"The motorcycling community and law enforcement have long sought a practical field test for measuring street motorcycle exhaust sound," said Ed Moreland, AMA vice president for government relations.

"Thanks to the hard work of the Motorcycle Industry Council, and the SAE engineers involved in the project, for the first time a simple field test is now available."

"The AMA maintains that few factors contribute more to misunderstanding and prejudice against street riders than excessively noisy motorcycles," Moreland continued.

"With the new SAE J2825 standard, street motorcyclists can now determine how quiet, or loud, their bikes really are."

Moreland added that the new standard follows a template established years ago with the SAE J1287 off-highway motorcycle sound test, a standard recommended by the AMA wherever off-highway motorcycles are operated.

The SAE J2825 on-highway motorcycle sound test procedure is similar to the one used for the SAE J1287 off-highway motorcycle test. The street bike measurement requires holding a calibrated sound meter at a 45-degree angle 20 inches from the exhaust pipe of a running engine.

The procedure spells out how to do the test with the bike at idle, at a predetermined engine speed ("Set RPM Test"), or by slowly increasing the engine speed of the bike, known as the "Swept RPM Test."

The SAE J2825 standard, prepared by the SAE Motorcycle Technical Steering Committee, recommends a decibel limit of 92 dBA at idle for all machines; or, using the Set RPM or Swept RPM Test, 100 dBA for three- or four-cylinder machines, and 96 dBA for bikes with fewer than three or more than four cylinders.

The creation of a new street motorcycle sound measurement procedure was a top recommendation of the 2003 National Summit on Motorcycle Sound, expressed by its Motorcycle Sound Working Group.

The AMA organized the National Summit on Motorcycle Sound to pull together riders and user organizations, representatives of the motorcycle manufacturers, the aftermarket industry, racing promoters, government agencies, and others to develop proposals regarding the increasingly controversial issue of excessive motorcycle sound.

"The J2825 test allows jurisdictions around the nation, struggling with complaints about excessive motorcycle sound, to set reasonable limits in accordance with the SAE standard," said Moreland.

"While the AMA supports the establishment of the SAE J2825 standard in America's cities, towns and communities, we will continue to fight efforts that single out motorcycles while still permitting excessive sound from other sources, such as loud cars and trucks, booming car stereos, poorly maintained generators, whining leaf blowers, and the like."

[dynodon]

excessively loud Motorcycles (and cars, boom box cars in general) are a pet peeve of mine. They aren't any safer, in fact, they can startle a driver into making a move that would not be anticipated, right into the bike!

 

Some bikers (Harley almost exclusively) use their LOUD pipes as a weapon sometimes, intentionally laying on the throttle when going by a car or other bike. At those times I wish for a multi horn air setup off a train or ocean going ship.

 

When the head of Harley himself says it is time to quiet the bikes a little, then you KNOW it is time.

[Dave77459]

The September '09 issue of the AMA American Motorcyclist magazine has a lengthy discussion of SAE J2825. (This link worked for me, p46 onward) In short, there is a easily performed standard test now, and I'd expect jurisdictions to adopt it.

 

Has anyone performed this test on a Venture (or better, RSTD) wearing stock Road King pipes? I'm not a loud pipe advocate, but I like the louder sound from my RK setup and am wondering if I need to worry about failing this test.

 

The article says H-D stock pipes pass, but I haven't compared whether they are louder on my bike.

 

Dave

[Flyinfool]

It is a step in the right direction.

 

But I'll believe it when I see a cop out there with a db meter and tickets issued that stand up in court.

 

I fully agree that ALL loud vehicles of any type or source need to be included somehow.

As far as boom box cars, the city that I live in has a new ordinance that a driver can be ticketed if the radio is audible at 50 feet from the vehicle. I have not heard of it being used yet. I am not sure if that includes the radio on a bike since there are no windows to roll up.

[Venturous Randy]

As far as boom box cars, the city that I live in has a new ordinance that a driver can be ticketed if the radio is audible at 50 feet from the vehicle. I have not heard of it being used yet. I am not sure if that includes the radio on a bike since there are no windows to roll up.

 

My thought on motorcycle radios is; if you are playing rap music and I can hear it from 10 feet away, you should have your motorcycle crushed and you spend the rest of your life in prision in solitary confinement being forced to listen to country music 24/7.

BTW, I don't care much for Rap music.

RandyA

[RandyR]

It is a step in the right direction.

 

But I'll believe it when I see a cop out there with a db meter and tickets issued that stand up in court.

 

I fully agree that ALL loud vehicles of any type or source need to be included somehow.

As far as boom box cars, the city that I live in has a new ordinance that a driver can be ticketed if the radio is audible at 50 feet from the vehicle. I have not heard of it being used yet. I am not sure if that includes the radio on a bike since there are no windows to roll up.

 

I expect most people can hear a normal conversation from 50 feet away. Maybe not perfectly, but hear it.

[LilBeaver]

...

But I'll believe it when I see a cop out there with a db meter and tickets issued that stand up in court.

...

 

I think the standardization of this is a great thing especially for safety concerns. (But also for the annoyances/distractions of some folks 'music' etc.)

 

I know for sure that in the state of Illinois anyway, a citation issued for excessive noise from modification of an exhaust system WILL hold in court just fine.

[Dave77459]

I expect most people can hear a normal conversation from 50 feet away. Maybe not perfectly, but hear it.

 

I am listening to a conversation on the far end of the office, 50' away and through two aisles of cubicles. Oh, and as I stand up, I see that they are inside the office with the door open.

 

Definitions of audibility are problematic.

 

Dave

[AKRefugee]

BTW, I don't care much for Rap music.

RandyA

 

RandyA

 

I am sorry to inform you but you are sorely mistaken.

You can not dislike "Rap music" because Rap is not music.

 

I believe you might mean Rap Noise.

 

 

[Venturous Randy]

 

I believe you might mean Rap Noise.

 

 

 

Excuse me, I stand corrected, as you are right!

RandyA

I also call it "rap crap"

[Snaggletooth]

Can't spell Crap without rap.