eplanto

I am looking to ride in District 37 events and am being told that my bike must be able to pass an exhaust sound decibel test 96dB Max. Can anyone tell me how loud the stock exhaust system is and has anyone passed a sound check with a Big Gun muffler?

Thanks!

Evin
2002 FE650e

ned37

i had a big gun on an '02 650, and don't think it was much louder than stock, but as far as passing sound check....

VOR165

I have a Big Gun on my 02 650. To me, it is no louder than a typical jap 450. But as far as specific decibels.... no idea

jdubb75

The stock exhaust will sound like braap braaap braaaaap. With the Big Gun it will sound like BRAAP BRAAAP BRAAAAAP! Sorry, I couldn't resist the chance for a quick joke.



I don't have any experience with a Big Gun on an FE650, but I have heard them on quads and I don't think they'd pass a 96db sound check...

If you already have the Big Gun on your bike and you have a smartphone, there are several free DB Meter apps you can download to check for yourself. They may not be as accurate as what would be used, but they should be pretty darn close. There is also a method used to check...something like idle from 2 feet away at a 90° angle to the exhaust, but I can't remember off the top of my head??? So, you may want to look up the sound check procedure to duplicate it as best as you can.

FYI - Here is the link to the LAB-Vegas FAQ.

https://labarstowvegas.com/faq

eplanto

Downloaded the dB app to my iPhone and found the AMA sound check guide. Will try it out tomorrow and let you know how it goes.

Watching the Seahawks game tonight and the stadium was at 98 dB.

Evin

eplanto

I used the AMA Supercross Sound Requirements:

C3 Test Site and Position of the Sound Meter
a. The sound levels will be measured with the sound meter/microphone fixed on a tripod, in the horizontal position, at the
rear of the motorcycle.
b. For the place and position of the motorcycle, ensure that there are no solid obstacles within 33 feet around the
microphone.
c. The sound meter will be positioned at a distance of 79 inches behind the motorcycle, with an angle of 45° away from
the centerline, on the exhaust side and at a height of 53 inches above the ground, with the sound meter level.
d. The 79 inch distance is measured from the point where the center of rear tire touches the ground.
e. It is preferred to make the tests on soft ground, not reverberating, i.e. grass or fine gravel.

Using Decibel Meter V2.2 on my iPhone placed on a tripod in grassy area positions appropriately I consistently got a max reading of 96 dB.

It should pass but I will try it again with some strategically placed steel wool to get it a few dB lower.

Alan

If second hand a repack should bring it down a db or two.

jdubb75

Be careful using steel wool for packing...it burns.

Huskyfatman

Big Gun has made several variations of mufflers, but assuming it's an '02 era add on, I put one on a KTM 520sx in '02 and it wasn't any louder than the stock pipe which didn't have a spark arrestor.

I also put one on a Husky 610 in and it was louder than the stock twin pipe set up but still much quieter than my stock YZ426 back then. I eventually replace the end cap with a newer version that had different sized caps for tun-ability.

Muze

Similar question different bike
99RD 501
Does the big gun add up by just booting on
Or is some carb work needed

Thanks for any info