Noise Resurfaces as Major Issue
Expect Major Enforcement in 2001

Author unknown.

Noise has always been one of the biggest reasons people don't like dirt bikes. And 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 problem.

So what happened? New 4-strokes are what happened, especially the super popular Yamaha 400/426 series. While right on the margin of legality, it is 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. The July issue of Dirt Rider 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!!! And 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 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. But even that thin thread of credibility about the YZ400/426 being a race bike, and the pipes are designed for closed course racing went out the window when you read the similar test on all of the pipes for the Suzuki DRZ 400.

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 Yamaha's. It makes very good useable power, but just a little less than the Yamaha. But what has 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 noise was 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, and 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 midrange, where most riding is done. None of them made more than one horsepower more than the stock pipe anywhere, except a couple had less than 2 horsepower more, one at extremely low RPM, and one at nearly 11,000 RPM. In fact, some of them were lower in power at almost every RPM. And a 1 horsepower gain at the ends of the powerband, while losing several horsepower in the most used midrange is not a performance increase at all.

Well what about that choked down Suzuki, it must have made major horsepower leaps with an aftermarket system, right? Sorry Charlie, only modest gains to be made here, a horsepower or 2. Barely noticeable. But, boy, EVERYBODY notices the difference in sound levels.

Where do we go from here? Well, the OHV Division just convened a committee to address the noise issue, which District Legislative Officer Bill dart is a member of. 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 be. 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 4-stroke exhaust systems has been recently circulated throughout that community, and anyone with an aftermarket exhaust on a 4-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 4-stroke, you might want to reconsider, especially if you can't get reliable data that it meets current laws. But if you want to use it long term, you want to look for pipes at or below 96 db, since it is almost a certainty that the noise limit will be lowered, the debate will be 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.

But 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 more enemies. Well, except for a few companies making significant money selling socially irresponsible products for big bucks-can anybody give me a believable reason why a 4-stroke exhaust system, with a simple head pipe and a simple can muffler, costs twice as much, or more, than a 2-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, more powerful, and lighter pipes. We need to make quiet COOL, instead of nerdy like the undertone in the enthusiast press is today. We need to harass our fellow riders with obnoxious pipes until they do something about it. Cause if we don't, all we are doing is digging our own grave.

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