(Clockwise) Reducer, deflector, radiator cap(Ed. Note: Variations range from the dB Dawg which deflects exhaust noise into the packing to a reducer that doesn't allow as much exhaust to escape at once. We also tested the radiator cap from Ignition Racing to keep an eye on our coolant temperatures while testing.)

If you're old enough, you've probably heard AC/DC's Brian Johnson screaming out at the top of his lungs that "Rock-"˜n'-roll ain't noise pollution!" No matter how old you are, though, you either have or are about to hear a lot of people screaming that ATVs are noise pollution! Now I think that there's just something about the sound of a properly tuned and fully packed silencer that's music to my ears, and I know that many other off-roaders feel the same way. However, a poorly maintained exhaust is a painful noise that not only hurts the ears of the user and anyone in the vicinity, but every ATV enthusiast in the entire country! In today's society, land access has become one of the greatest obstacles we as ATVers face. The anti-ATV crowd focuses on two common areas in hopes of limiting — or, even worse, eliminating--our access to riding areas. Those areas are noise and dust. While the sound of a sweetly tuned exhaust may be pleasant to you, it may well be grating and irritating to your next-door neighbor. So how do we resolve this problem?

GYT-R offers a complete end-cap design to knock down the exhaust noise for their add-on exhausts.

The Problems

In today's society, we, the ATV community, face challenges that were non-existent only ten years ago. The combination of urban sprawl and the advancements of four-stroke technology have contributed to many of them. In the days of the two-stroke, noise was not as big an issue. Why was that? Well, while it may be true that the decibel readings for two-strokes is generally about the same for four-strokes, the wavelength and frequency of the tones are vastly different. The sound emitted from a two-stroke doesn't carry very far in terms of the human ear. This is especially true as we get older, because we don't pick up the higher frequencies as well as we did when we were younger. That's why the sound of a two-stroke, while loud when it's near you, quickly fades away the further you go from it. On the other side of the spectrum, however, is the four-stroke motor. Its wavelengths carry for very long distances and are very audible to the human ear from very long distances. This is where non-ATVers tend to get angry at us because, unlike a two-stroke engine, a four-stroke can be heard long before it can be seen.

As difficult as this may be, we in the ATV community need to change one of our most common (and, to some, most cherished) perceptions: more noise equals more power. Although this perception is completely unwarranted, it's easy to see how it came about. Stock exhausts are very quiet and choke up the motor. Sliding on an aftermarket exhaust results in making much more power, but also results in making much more noise. Ergo, some people have come to believe that you can't have one without the other. Because of this false perception, the aftermarket industry is being stabbed with a double-edged sword. Companies realize that noise levels need to come down if they want their customers to have anywhere left to be able to ride, but at the same time they're in business to sell products their customers want to buy, and the fact is that customers by and large want loud exhausts. We were talking to a rep from one of the major exhaust manufacturers, and we were told that although the company could make an exhaust that was just as quiet as stock while still making the same power as its current model, it wouldn't be offering that unit "because no one will buy it!" Sadly, people still believe that if they're not making noise, they're not making power.

The Solutions?

The ATVA is stepping into the picture now and is also helping to force the issue by mandating a lower level of sound levels at the professional level. Because people tend to follow the practices of the Pros, the ATVA is hoping that, when the pros begin to lower their noise levels, the amateurs will do likewise. Other racing organizations are following suit, both at the local and national levels. While this helps on the organized racing end of the spectrum, local DNR officials are also cracking down on the trails.

Slide in the dB Dawg into the silencer / tighten the 2 set screws and we're ready to go with a quieter ride without loss to powerAs a responsible ATV rider, you need to ask yourself before each ride, "Is the sound I'm about to make going to really bother people in my surroundings?" You should also take into consideration installing one of the common quiet cores, or similar devices. Although that can result in the loss of a small amount of horsepower, that's an amount you most likely never tap into during your ride anyhow. It all boils down to being accountable for your own actions!

One of the most overlooked and yet simplest ways to keep your exhaust noise to a minimum is to make sure you maintain good packing in your silencer. Most aftermarket exhausts are designed to come apart easily so that they can be repacked easily. You have four basic options when it comes to packing your silencer: swipe a little pink fiberglass insulation from your dad's garage (which normally only lasts about one ride, if that long), buy some specially made fiberglass packing material, buy packing material that resembles long strands of string with feathers on it or buy replacement packing canisters. While the pink fiberglass insulation is a quick and easy fix, it also quickly falls apart in today's four-strokes and doesn't work as well as it did years ago in a two-stroke exhaust. The fiberglass packing material works well, but doesn't reduce noise as much as the remaining two options. The white material that looks like strings with feathers on it is one of the most useful ways of knocking down the noise and usually holds up as well as any of the other materials. The last method is definitely the easiest: buy a pre-made canister of packing material that you simply slide into your exhaust canister and that fits perfectly between the center core and the outer can. This method is the simplest (and available for most popular exhausts), but its downside is that it's the most costly. No matter what method you choose, though, you must always remain aware of whether or not your exhaust needs to be repacked.

While aftermarket exhausts are the main areas of noise pollution, the manufacturers are not ignoring this problem. They realize that if we don't get the noise levels down, pretty soon the only things we'll be out riding are our bicycles and electric scooters! Many of the major manufacturers have spent huge sums of money in research and design to find a viable solution to the problem. This issue has also brought new products into the market and new players into the ballgame.

Once inserted, the dB Dawg rests flush with the end of the silencer for a clean fit.When it comes to quieting down the exhaust, different companies have found different paths that work with their products. DRD (Dubach Racing) has redesigned the end cap that comes off the end of its silencer and also changed the material. The combination of the new design and the magnesium material that makes up the end cap has helped bring down the noise output by a few decibels without sacrificing any power. In addition, DRD offers an additional quiet core that helps to direct more of the sound waves into the packing instead of straight out the silencer, bringing the exhaust tone much closer to the stock levels. Other companies offer their version of a quiet core that reduces the size of the output opening. This definitely quiets down the noise, but it does sacrifice some power.

Among the new players brought into the market by trying to solve this problem is Ignition Racing. Ignition's parent company has been in the automotive exhaust business for many years, so dealing in exhaust products is not new to them in any way. Instead of making an intricate, expensive product, Ignition went the other way and used the KISS principle (Keep It Simple, Stupid!). The end result is the dB Dawg, an insert that fits into the end of your exhaust and quiets your ATV down by 6-10 dB--that's almost enough to bring it back down to stock noise levels! Ignition claims that the dB Dawg doesn't cause any significant power loss (as long as you re-jet) compared to running with a free-flowing exhaust. The dB Dawg comes in a few generic sizes to fit most applications and a few custom-made to fit specific applications. The principle behind the dB Dawg is not to just reduce the exhaust outlet, but to make sure to deflect as many sound waves into the exhaust packing as possible before allowing the exhaust to escape. We were intrigued enough by this item to want to test one out to see how it worked (or didn't work).

We Test One

Installation was a snap--slide it in and tighten two set-screws (we recommend some Loctite and high-temp silicone if you plan to leave this part in for the long term). Once in, we needed to adjust our jetting slightly to account for the change in airflow. Just for curiosity's sake, we wanted to know if this additional back pressure was going to cause any extra build-up in heat in the motor, so we also installed a thermostat on the radiator (also available from Ignition Racing). This thermostat replaces the radiator cap and allows us to keep an eye on the coolant temperatures. The end result: power was very close to what we had before installing the tip, but it was very deceiving because things were so much quieter than before. There was a less than five-degree difference in coolant temperature than there was before, so that was no problem. It's products like this that prove we can still get really good power out of four-strokes without making an obscene amount of noise.

Just remember the next time you're either in the market for an ATV exhaust or plan to modify your stock exhaust, that looks and buying what a big-name rider is using for an exhaust aren't factors on which you should base your choice. The choice should be made taking into consideration your surroundings and the effect that you may have on those surroundings. A closed-course racer can get away with emitting a louder sound than someone who rides around residential or business areas, or trail rides on public land that are shared with other users. More noise does not always mean more power; it may just mean less thought in the design of the product itself. If we begin to police ourselves, keep the noise levels down and keep our silencers packed, we'll be able to continue to enjoy the sport of ATVing for many years to come.