Best way to get down to 96db???

Message

Crazie · #11 Post by **Crazie** » Fri Dec 12, 2008 1:06 am

Exhaust brake...lol.

Kuma · #12 Post by **Kuma** » Fri Dec 12, 2008 1:58 am

I've looked into this a little more, found this:
SAE J1287 I believe is what most would use as a standard to measure,From what I see in Appendix A.1
you should be getting a +/- 1.5 dB tollerance. If they are using 1/2 of redline then you should get a 3 dB tollerance.

An alternate meathod for engine speed is in A.7, four stroke is 250,000/stroke in mm, 61 mm stroke should be tested at 4098 rpm if you can convince someone that it has more stroke than that then it will drop the speed some more.

This info may not prevent a ticket but it could help you beat one.

Also found that Oregon dunes have a 93dB limit

cannondale27 · #13 Post by **cannondale27** » Fri Dec 12, 2008 2:53 am

93db is tough to get. My YFZ and Cannondale with only 3 SuperTrapp discs just made 93db and that is really choking it off. A stock toaster will just barely make it. If you go stroker or big bore even forget it. Wont happen. Buddies 450R with a stroker crank and exact same pipe as mine with 3discs blew 98db. He had to use a insert and the discs. Burned up packing within 20 minutes from it getting so hot. My Raptor with GYTR quiet cap actually melted the aluminum! Looks like if it gets that bad the only choice may just be those old FMF round exhausts. Those like to rot out and blow the seam at bottom. Might have to figure something out for that issue.

m_mcgranahan · #14 Post by **m_mcgranahan** » Fri Dec 12, 2008 4:54 am

Hi,

Thanks for all the input. This is a new law Jan 1, 2009 for AZ (Sticker and noise limit etc) I really wonder if they will/can enforce this at private owned race tracks? I'll have to look at the law. It is so strange I can buy a gun out here no questions asked, I can buy a holster and carry it around to the store, gas station, church you name it and no regulation AT ALL! I can go shoot it on designated public lands and I wonder how many db it would be??? But take a quad out and be loud, and there goes the money out of my pocket

Very frustrating!!!!
And slightly stupid. Sorry had to vent...

QUOTE (cannondale27 @ Dec 12 2008, 02:53 AM) <{POST_SNAPBACK}>

93db is tough to get.My YFZ and Cannondale with only 3 SuperTrapp discs just made 93db and that is really choking it off.A stock toaster will just barely make it.If you go stroker or big bore even forget it.Wont happen.Buddies 450R with a stroker crank and exact same pipe as mine with 3discs blew 98db.He had to use a insert and the discs.Burned up packing within 20 minutes from it getting so hot.My Raptor with GYTR quiet cap actually melted the aluminum!Looks like if it gets that bad the only choice may just be those old FMF round exhausts.Those like to rot out and blow the seam at bottom.Might have to figure something out for that issue.

Crazie · #15 Post by **Crazie** » Fri Dec 12, 2008 7:16 am

I had no idea they were implementing a sound limit with the sticker law...sigh! I think California is rubbing off on us!

I think we'll only have to worry near residential areas. In Yuma at the foothills, everyone rides everywhere from their houses (gas station, etc.) and we have a big riding area less than a mile away. I'm wondering how many issues we'll have here, since there are Sheriffs that live in the neighborhood.

2mike18 · #16 Post by **2mike18** » Fri Dec 12, 2008 7:34 pm

its unfortunate that enviromental laws are killing off our sport one regulation at a time. I live about 30yrds off a state trail and i hear sleds and quads all the time all day and all night sometimes they wake me, but I knowingly bought this place because of trail convience so I think everytime someone goes by and wakes me "man that should be me out there dang 4am work" lol I actually think now more than ever is the time to get active and start or join an atv club so we can protect our interist to ride. across the bridge in duluth minn it got to the point you cannot even ride any atv on the trails so I moved across the bridge to superior wi a whole 6 miles from my last place. now the only concern is noise which all 3 of my quads will fail to pass. SORRY about the rant but I love to ride as much or more than the next guy and it seems to get harder every year to keep that right.

NotSoYoungAnymore · Fri Dec 12, 2008 8:53 pm

CA has a 96dB limit at the State run SRVA's but the private tracks are not limited, unless they are near housing.
We run a series that is 90% on private tracks, but one of favorite tracks is Hollister Hills GP and there we all have to come down 99dB or lower. Thank fully it's only twice a year. It's somewhat hilly track and you can sure feel the power loss.
I understand the WORCS series is going to 96dB for the pros in 2009. The amateurs get a year's reprieve at 99dB, in 2010 every WORCS racer will be at 96dB.
Sound limits are coming whether we like it or not.

peterock · #18 Post by **peterock** » Fri Dec 12, 2008 10:02 pm

Thing is, they need to first enforce the pros........

UpsMan · #19 Post by **UpsMan** » Sat Dec 13, 2008 8:45 pm

QUOTE (peterock @ Dec 12 2008, 04:02 PM) <{POST_SNAPBACK}>

Thing is, they need to first enforce the pros........

Right. When it gets enforced at that level, I'm sure the technology will grow by leaps and bounds immediately. All it takes is money. I'm sure the exhaust manufacturers could make quiet pipes that also perform, but why would they if they don't need to? Also, I have been very happy with my Weaponmx pipe. Still looks like new. I've never tested the db but I'm sure it is below 99, not so sure about 96. I do think it is choking power some, but what can you do?

NotSoYoungAnymore · Sun Dec 14, 2008 3:49 am

That's what it will take to get some innovation in exhaust technology.
Funny thing about WORCS, Hollister Hills has been on their schedule the past several years, and it has by far the toughest noise enforcement. But they dropped it from the 09 schedule. So, maybe they think it is going to take awhile to get the pros to conform to the new dB limits.