AMA's Bill Dart on Thumper pipes; must read

[maicomotoman]

If we act like good neighbours always considerate of others then they will back us or at least leave us alone. I'm with you.

Count me in too :) Although I (unfortunatly) think it will take more work than just being good neighbors. That's where it starts though. Cheers!

 

[mtngoat]

Please forgive me if this post re-states positions or appears mis-directed. I wrote it as a "stock" response to several other threads on other sites running on this topic and copied here.

Balancing diverse rights is tricky business. A growing population, OHV popularity and dimishing public lands is creating a conflict where a no-compromise stance will not work and should not be taken.

Noise is not a diversionary issue; it is a core issue. Loud thumper propogation is making it worse. I've tested several bikes and seen sound levels that are 2-3 times the legal limit (such limit has been in the Cal. Vehicle Code for a long time, just not enforced).

The exponential nature of decibels means that 3dBs is a doubling of sound. The 85-90db range is considered hazardous to hearing, but of course we're wearing helmets, the people we ride by are not. There's a lot of bikes with aftermarket pipes approaching the 110 level. That level of noise will hurt our sport and we cannot establish our innocence by the guilt of others (e.g. Harleys, planes, chainsaws, whatever)

More and more people will use public lands we ride. Most of them have no "green" agenda and have the right to use and enjoyment. Everytime we affect their rights with un-reasonable noise, we've turned a neutral party into an anti-bike advocate.

Now, I don't like that a 96dB level is being considered, when the 99 level was never enforced. And, I think there's plenty of "over-reaching" by those that oppose us. But, I also know that people on the battle-lines of these issues (like Bill Dart) have to deal with a lot more issues than the ones we dissect and criticize. They need our support.

Complaints without action may just as well be complacency. Take action however you see fit, but consider: (a)learning how loud your bike is; (b)if too loud, what you can do to quiet it; (c) spreading this attitude to others; and (d) throttling back the noise in the presence of others you encounter on public lands.

 

[geremacheks]

In the case you meet horses and their riders on the trail, try to let them pass by pulling your bike clear of the trail and shut it down, so there is no sound at all. Equestrians appreciate this if you are able to do it. And it is just courtesy. Most everyone knows you can't trust a horse. And there may be a novist rider on that horse.

Hey, and it's not nice to roost in horseapples, either. (Wow. I feel so benevolent. I suppose somebody out there wants to tell me to stuff horseapples up my exhaust.)

On a sidenote: those heavy horses sure can tear up a soft terrain trails.

 

[FoxRacing023]

i think how fast people ride is all in their head, if somebody pours $500 into a pipe that will give your bike "20% more hp" they beleive it. i bet if u took a aftermarket system and made it look like the stock pipe the person would think it was a stock pipe. i was recently at a race and there was a 250F with the loudest pipe i had ever heard, it made the ground shake, it was crazy. the guy smoked the competition but he could of done this with the stock pipe.
if u ask me people ride faster cuz they think the exaust is giving their bike more power when all its doing is giving people headaches and making them run inside to call the police. i know MX racing is a big head game because i got boots and graphics and i was a whole lot faster instantly.every one else has allready said what i just did but hey, i felt like putting my 2 sense in ;)

 

[harescambler]

I have a 99 wr400. when I bought the bike (used) it had a White Brothers e-series pipe and header. It has the straight tip on the end and its way too loud. I've called several places (ads in dirt rider etc..) and can't find where I can get the disc type tip to quiet the bike. anyone know where I can find the disc style tip without having to get a new header??? At a race it registered 109db!! Not sure how accurate it was but I don't want to show at a GNCC and just get sent home. Any help would be appreciated.

 

[mtngoat]

www.whitebros.com

Or check with local dealers listed on their website. Ordering direct from White Bros costs full retail. Many dealers discount their retail prices.

The discs alone will not get you below 100dBs (I've tested my buddy's YZ with an E-Series). The discs and the new quiet core insert from White Bros. might.

 

[wardy]

bump

good topic which with all the new bikes being bought this winter, sound should be considered before strapping on a new pipe. AMA did this fall at congress start the process for 96db. Our riding park in IL will start looking real hard at loud machines, bought a db meter in august.

wardy

 

[BSWIFT]

Good call Wardy.  I myself would like a quieter exhaust for Brutus(03YZF450).

 

[chopair]

Best Thread that I have seen on any forum. Congratulations to all!

Mtngoat, I tried to send you a PM via this forum, but did not "have permission" to do so?? Don't know why yet, but am looking into it.

Please PM me or email me and I'll provide an address to send the sound testing manual.

Regarding the White Brother's Quiet Core insert. I installed it on my XR416. It took the sharp edge off the exhaust note and definitely altered the throttle response. After 4 months I remove my pipe and found the tube and screen portion rattling around in the core of the pipe. The two small welds that held it to the plate had failed. Oddly enough, I didn't notice a great difference in the sound level of the pipe when it occurred.

RH

 

[beer_stud_76]

i realize this is an old thread but i must jump to the defense of loud pipes. of course everyone's definition of "loud" is different, and 96db will still be too loud for some.

however, here in western Wa, you don't see a dirtbike comming the other way on a trail from way off. in fact 99% of the time you don't seem them till you have met at a blind corner. in addition to my fairly loud XR600 i ride my mountain bike on these trails and my old lady rides horses in areas often used bike dirtbikes. both of us actually LIKE the loud bikes. we hear them and can get out of the way. i can't tell you how many times i've been early pasted head long by one of you "considerate" quiet dirtbikers, but i can say that i've never had a close call with a loud bike. its a legitimate safety issue. loud bikes save lives. period. there can be no counter argument to this.

maybe in the wide open desert where you can see a dust cloud or something from a long way off this is a moot point. and i can see how an MX track packed with extra loud bikes might be a nuisaunce(sp) to the nieghbors. but out here in the dense muddy woods what sound there is doesn't travel far.

as far as i'm concerned, i'd rather ride a quiet bike. but me and my bike wiegh a combined 600lbs or so. this going down a trail even at a modest pace is enough to kill a man or break a horses' leg or whatever. so far, and often because of my loudish bike, i haven't had a single scary moment with another trail user.


jeremiah

 

[geremacheks]

Quote: "Loud bikes save lives, period. There can be no counter augument to this."

I think this was coverd already with many counter arguments. But if you want another one, maybe this one wasn't covered:

Loud bikes can cause riders, and anybody nearby, to gradually lose their hearing. This can cause all kinds of safety problems, not only when riding, but in general everyday life. If you can't hear, you can get killed by simply walking across the street. It's a "mute" point.

 

[beer_stud_76]

what? i can't quite hear ya sonny! could ya speak up!

 

[bike811]

When I bought my '02 CRF I debated whether to buy an aftermarket spark arrestor type exhaust system, buy a spark arrestor muffler for the stock pipe, or just a spark arrestor end cap. I use the bike for woods riding as well as some motocross and HS. I did not want any issues with the rangers and I knew I was not fast enough of a rider (few are) to take full advantage of all of the power I already had. I finally did buy an FMF quiet core system after badly smashing the stock stuff.

I put a lot of thought (and money) into this issue. I have to say that even though the new pipe may be slightly quieter than stock, I wish it were a lot quieter. I can not tell any significant difference in power either (maybe a little less on bottom) but atleast I don't need to worry about the S-A thing anywhere I go.

I would rather not have a muffler any larger or longer than what I have now. When sliding into a tree in the tight woods, or wrecking, the muffler and or sub-frame is more likely to get bent and cause problems during a ride or race.

If it were not for the weight and bulk I would prefer a quieter muffer, but to be significantly quieter without a significant decrease in power a muffler must be larger. There can be some varation in performance due to the accustic design between modern mufflers of the same size - but not a significantly large difference - KTM EXC mufflers are not long (2 or 4 stroke) for looks.

Four stroke engines fire half as often as two stroke engines so the sound frequency is much lower and travels through objects (such as a muffler) more easily.

The longer I ride the less I like loud bikes. I no longer care how "good" an engine sounds when I ride even though I do like the sound of a good engine. I just want it to go fast. With dirt bikes a little horsepower is far less important than the skill of the rider. I have ridden behind loud bikes in the woods and it can get old after a while no matter how good it sounded in the parking area. My own bike noise gets old after listening to it long enough.

I hate to say it but riding motorcycles (or even driving cars), particularly on public land or in a public environment is a privelige determined by elected or executive government policy, not a constitutionally assured right. Some things are assured in the constitution but riding dirt bikes ain't one of them. If we don't compromise a little on the noise issue we will not be able to ride anywhere.

 

[Rodzilla]

Quote: "Loud bikes save lives, period. There can be no counter augument to this."

Glad this thread has popped back up!

We'll all be safe since there won't be anywhere to ride!

 

[flynbryan]

Quote: "Loud bikes save lives, period. There can be no counter augument to this."

:silly: ............Idiot........ :flame:
Have fun listening to your loud bike in the garage........cause you won't be riding it anywhere if the biking population as a whole takes this approach. Go to a nascar race if you want LOUD . I want to be able to continue riding my motorcycle.

 

[whyz]

I use to ride 2 strokes in my field until I got my Baby-F, That was the first time my neighbor came out and said wow that bike is loud,
"I can' t even hear my TV"! and did one of these moves :| and walked off. I think he was pissed. And it is loud.I agree.
So I went and bought the Q and a SX Power Bomb header.
Moocho quieter,Bottom feels the same,
mid - top feels like it pulls longer(but who knows)
I like it mellow and that's what it did.
Now I'm back in my field practicing and my neighbor likes it too
and so dose my wife :scream: :confused:

I always thought that a 4 stroke exhaust was just loud.
--> I mean--< Why.

 

[Teknik]

Just a word on the "overly restrictive " stock WRF pipes, the ones that must be changed for a YZ pipe or you are just an idiot, my business supports the Official Yamaha off road team down here in Australia and we actually use the stock pipe for tight enduro (woods) events for it's superior bottom end response.
There are mufflers around that do work and are quiet. Hell I even sell them. 92DB on a YZF250 with the same power characteristics as a 426/450 pipe on the 250. But guys still love loud top-end-only pipes. Must be a testosterone thing.

 

[Rich Rohrich]

Originally posted by Teknik

There are mufflers around that do work and are quiet. Hell I even sell them. 92DB on a YZF250 with the same power characteristics as a 426/450 pipe on the 250

Care to back that up with something other than your good word?

 

[JWW]

Maybe you have different pipes. I know that Canadian and US models have different pipes.

FYI.... Some of us are forced to change. Mine was not legal for public land.

 

[motometal]

a side note-I believe that cam profile/timing and cyl. head design also plays a role in decible level.&nbsp;

 

[p.bowman]

Originally posted by mtngoat
This may not be what we (or others) want to hear, but we need to listen up.

NOISE RESURFACES AS A MAJOR ISSUE

By Bill Dart, AMA District 36 Legislative Officer

Noise has always been one of the biggest reasons people don't like dirt bikes. I am not talking about just environmental groups that don't like OHV recreation on general principles and philosophy, either. We can deal with almost every issue they raise. We can deal with water quality, air quality, erosion, wildlife issue, botanical issues, archaeological issues, and user conflict issues. Often, all of these are just surrogate issues for the real, underlying reason; nobody likes noisy dirt bikes.

I don't think we will ever be able to satisfy environmental extremists, but we need to quit making the general public mad at us over noise. Susie Soccer Mom doesn't like noisy dirt bikes. Joe Six Pack doesn't like noisy dirt bikes. Virtually every single elected official, appointed regulator or public land manager, doesn't like noisy dirt bikes. I don't like noisy dirt bikes.

Noise has always been a major issue, but until a couple of years ago, the trend was towards much more quiet dirt bikes. Water cooling, tighter engine tolerances, better induction systems, and better mufflers had brought the sound level of most dirt bikes down into the mid to low 90 db range by the early 90's. Most of the older, louder air cooled bikes have gone to that big riding area in the sky, or are rusting out behind the shed under a tarp, and noise complaints had dropped off as a major issue.

So what happened? New four-strokes are what happened, especially the popular Yamaha 400/426 series. While right on the margin of legality, they are still too noisy right out of the crate. But the problem really gets bad when an aftermarket exhaust system is installed, which it seems about 90% of these bikes have today. Dirt Rider magazine did testing for power and sound levels on all of the popular exhaust system available for the Yamaha 400/426 series, as well as the new Suzuki DRZ400. According to their testing, the Yamaha measured 100 db stock, barely within the 99db, plus or minus 2 db, mandated by California law. But none of the aftermarket pipes tested came in below 102db, and most were between 104 and 106 db. This means that NONE of the aftermarket pipes for the 400/426 are legal to use anywhere on public lands in California, not even for racing.

"But, those are racing systems," is the response from the aftermarket companies. Baloney! AMA rules have a maximum noise level of 99db. None of them are legal for AMA amateur racing. And what about other private tracks that aren't AMA? Well, many of those tracks have been shut down. Why? Because people hate noisy dirt bikes! I asked most of these companies if they had ever tried to get a permit for a new track, as I have several times. I bet you can guess the single biggest reason why many tracks are never granted permits. If you guessed noise, you are starting to get the drift on the noise issue. Even the thin thread of credibility about the YZ400/426 being a race bike and the aftermarket pipes were designed for closed course racing, went out the window when we read a similar test on all of the pipes for the Suzuki DRZ400.

Unlike the Yamaha, the Suzuki doesn't pretend to be a race bike. It is a recreational trail bike that would cost more to make truly race worthy than a couple of Yamahas. It makes very good useable power, but less than the Yamaha. What really impressed everybody who has heard one is just how quiet it is, yet it still has outstanding performance. Dirt Rider tested it at 90 db with the stock pipe, which is very quiet, and it still puts out over 40 horsepower. For comparison, the latest 426 Yamaha has about 45 horsepower and the Honda XR 400 puts out just a little over 30 horsepower.

Well, the DRZ400 noise got just about as bad as the Yamaha, once the stock pipe was replaced. Not a single one is AMA legal, according to the Dirt Rider data. Only one is barely California legal, the Stroker spark arrestor model, at 100 db. All the rest are between 102 and 104.

But, what about all that extra power that comes with the noise, isn't that reason enough? Well, in the case of the Yamaha, none of the pipes even matched the stock pipe's midrange, where most riding is done. Most of them made less than one horsepower more than the stock pipe. A couple made less than two horsepower over stock, one at extremely low RPM, and one at nearly 11,000 RPM. In fact, some of them were even lower in power than stock at almost every RPM. A one horsepower gain at the ends of the powerband, while losing several horsepower in the most used midrange, does not amount to a performance increase.

What about that choked down Suzuki? It must have made major horsepower leaps with an aftermarket system, right? Sorry, Charlie! Only modest gains were made, a horsepower or two. Barely noticeable. But, boy, EVERYBODY noticed the difference in sound levels.

Expect Heavy Noise Law Enforcement in 2002
Where do we go from here? Well, the OHV Division just convened a committee to address the noise issue, of which I am a member. They have been charged with developing a recommendation for a new sound limit law. The Motorcycle Industry Council has already recommended that level be lowered to 96db, with no plus or minus variation, as a level the industry can comply with. This is likely to be the highest the new law will allow.

"But so what?", you might say. Nobody is enforcing sound limits anyway. Well, things are changing in this field as well. Noise enforcement will be a priority next year. The OHV Division will be providing all of the test equipment needed to every agency that requests it, and the MIC has updated their technical test data manual, so that all models can be properly and legally tested. Additionally, with law enforcement grants exploding this year, and the new state emphasis on noise enforcement, you can expect rigorous field enforcement this year all over the state.

Due to the new emphasis on law enforcement, and the enhanced communication between all of the various law enforcement agencies dealing with OHV's, the sound level of the aftermarket four-stroke exhaust systems has been recently circulated throughout that community, and anyone with an aftermarket exhaust on a four-stroke will be automatically suspect, and the officer will have probable cause to do a stop and sound test.

If you have been considering buying an aftermarket exhaust for your four-stroke, you might want to reconsider, especially if you can't get reliable data that it meets current laws. If you'll want to use it for the long term, you'll want to look for pipes at or below 96 db, since it is almost a certainty that the noise limit will be lowered. The only debate will be about just how much it will be lowered. If you already have an aftermarket system that is over the legal or AMA limit, I would urge you to demand a refund, since it is not even legal for AMA-sanctioned, amateur closed-course racing.

More important than being technically legal, if we really love to ride and want to protect our sport, we need to do everything we can to reduce noise well below the legal limits. We need to make friends, not enemies, and all we really get from noise are more enemies -- except for a few companies making significant money selling socially irresponsible products for big bucks. Can anybody give me a believable reason why a four-stroke exhaust system, with a simple head pipe and a simple can muffler, costs twice as much or more, than a two-stroke system?

Let's bring back the programs that brought the noise levels down before. TEAM STEALTH. Less Sound = More Ground. We need to reward companies that make quiet yet more powerful and lighter pipes. We need to make quiet COOL, instead of nerdy, like the undertone in the enthusiast press does today. We need to harass our fellow riders using obnoxious pipes, until they do something about it. Because, if we don't, all we are doing is digging our own grave.