Michigan Exhaust Law


I heard that it did pass and the fine is $250, havent heard about any hassling yet but when i finish mine here in the next week or so I may have problems as mine is at 97db (tested this weekend) damn race pipes :o|



Bill
 
I haven't heard of anyone getting checked in the Cadillac area, but I saw on the news somewhere up north of here they were showing the DNR stopping people but they didn't say anything on the news about people getting ticketed for exhaust.
 
I was stopped by a Sheriff earlier this year. He just looked at my trail pass and sent me on my way. But the Viper with the Bender pipes isn't all that loud anyway. He even went as far as directing me to a spot on the trail to take the Viper out and open in up to check jetting.
 
Where did you get it tested?



billbies said:
I heard that it did pass and the fine is $250, havent heard about any hassling yet but when i finish mine here in the next week or so I may have problems as mine is at 97db (tested this weekend) damn race pipes :o|



Bill
Click to expand...
 
I have a friend with a car audio shop with a db mic portable setup so I asked if he could bring it over just for curiosity sake bc my setup is "unique" to say the least with a bender racing prepped 600 srx bottom end with 738 cylinders and pistons with 600 bender one off race pipes with a manipulated stock 700 cdi :bash: so we knew it was going to be "louder" than a normal piped or canned srx and we wanted to see what it actually came out to.


You can look them up on ebay or radioshack just a basic db meter should get you close so you have an idea and they are relatively cheap



Bill
 
Guys, make sure you educate yourself on this subject - the SAE J-2567 test is suppose to be performed on a stationary vehicle with a DB meter 48" above the ground and 4 meters (approx 12') from the exhaust - the article in the MSA indicates that the test is 20" from the exhaust - that is not correct - if you get stopped and are checked, make sure they are testing you correctly - if not, take a picture or document how the test was performed - they will be banking on your ignorance of the law - if sort of piss*s me off that the MSA is misleading us in how this test is suppose to be performed - I'm not advocating loud exhaust in any way, but if you have a legal exhaust that is illegal because of how the test was performed - that is just not right!!!
 
yammiman said:
Guys, make sure you educate yourself on this subject - the SAE J-2567 test is suppose to be performed on a stationary vehicle with a DB meter 48" above the ground and 4 meters (approx 12') from the exhaust - the article in the MSA indicates that the test is 20" from the exhaust - that is not correct - if you get stopped and are checked, make sure they are testing you correctly - if not, take a picture or document how the test was performed - they will be banking on your ignorance of the law - if sort of piss*s me off that the MSA is misleading us in how this test is suppose to be performed - I'm not advocating loud exhaust in any way, but if you have a legal exhaust that is illegal because of how the test was performed - that is just not right!!!
Click to expand...

Great point ;)!

I questioned the MSA and here is the response I got:

You are completely right. When I wrote the column I was in a rush, because I was late for the deadline and I mixed the 20" test for dirt bikes and boats. I did get called on this and looked it up on Monday. I will get it changed on the web tomorrow when I meet with our web guy!

Thanks For Keeping Me Honest!


Bill Manson
Executive Director
Michigan Snowmobile Association
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Mountain Performance's site says my Benders are 94dB. I wonder how they measured that. And if I could pass with mine?
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94db is a long way from 84db. I'm trying to talk the local police into borrowing thier decibel meter.

Since the range of intensities which the human ear can detect is so large, the scale which is frequently used by physicists to measure intensity is a scale based on multiples of 10. This type of scale is sometimes referred to as a logarithmic scale. The scale for measuring intensity is the decibel scale. The threshold of hearing is assigned a sound level of 0 decibels (abbreviated 0 dB); this sound corresponds to an intensity of 1*10-12 W/m2. A sound which is 10 times more intense ( 1*10-11 W/m2) is assigned a sound level of 10 dB. A sound which is 10*10 or 100 times more intense ( 1*10-10 W/m2) is assigned a sound level of 20 db. A sound which is 10*10*10 or 1000 times more intense ( 1*10-9 W/m2) is assigned a sound level of 30 db. A sound which is 10*10*10*10 or 10000 times more intense ( 1*10-8 W/m2) is assigned a sound level of 40 db. Observe that this scale is based on powers or multiples of 10. If one sound is 10x times more intense than another sound, then it has a sound level which is 10*x more decibels than the less intense sound. The table below lists some common sounds with an estimate of their intensity and decibel level.

SourceIntensityIntensity Level

# of Times Greater Than TOH

Threshold of Hearing (TOH)1*10-12 W/m20 dB100Rustling Leaves1*10-11 W/m210 dB101Whisper1*10-10 W/m220 dB102Normal Conversation1*10-6 W/m260 dB106Busy Street Traffic1*10-5 W/m270 dB107Vacuum Cleaner1*10-4 W/m280 dB108Large Orchestra6.3*10-3 W/m298 dB109.8Walkman at Maximum Level1*10-2 W/m2100 dB1010Front Rows of Rock Concert1*10-1 W/m2110 dB1011Threshold of Pain1*101 W/m2130 dB1013Military Jet Takeoff1*102 W/m2140 dB1014Instant Perforation of Eardrum1*104 W/m2160 dB1016
 
Well that's what I was wondering, how did they do the measurements to come up with 94dB? If the DNR is gonna measure it 12 feet away maybe it won't be so high? I don't know. I do know I'm not getting rid of my pipes. If I had already been able to ride with them for several years or something maybe I'd just take them off (but I doubt it). The first thing I thought to myself when I first put these on was I thought they'd be a lot louder than they are. I'm just gonna avoid the places that I know they'll have checks set up at. :2strokes:
 
I almost forgot, you can get this sound level meter from Radio Shack for $50. Too bad Wal Mart doesn't sell one, I'd check my exhaust with it and then return it. You might be able to do the same thing at Radio Shack but they really don't like returning stuff for a refund.
 
^^^^^Either of these two will work^^^^^ as a good baseline or general idea.


The bad part in all this is the setting when this test is done is going to make a huge difference as to the reading as well, if you are on hardpack or a parking lot it will be a lot louder than if you pull off the side of the trail in powder and also if you are in an open field or area vs. being near buildings or wooded area etc. thats what makes this law so skewed bc the enviornment in which the test is done will/can directly effect the outcome of the test.

Just my .02 from my experiences with dirt bike enduro riding which they had a db rule and it was contested all the time bc of the different reasons above


Bill
 
triple pipes just don't meet the law - I tried with the Hauck / CPR pipes I had on the sled I parted and they were all of 94 decibels. Bottom line is you cannot modify your exhaust - a shop owner that sells pipes said in WI if they have you pop your hood and you have modded exhaust you're going to get a ticket. That simple here. The way the law is written it needs to pass the test and be stock.

On the other hand - after joining the local club this year - I know from the other guys in the club that the #1 and #2 reasons for trails getting closed are noise and people running off the trail.
 
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