There are many reasons why ATV owners want to quiet the exhaust noise on their machines. In this post, we’ll take a look at different ways you can achieve this.
We’ll also have a look at some pros and cons of quietening the exhaust, and how well it really works. This will allow you to consider whether the benefits outranks the downsides and to decide whether it’s worth it for you or not.
1. Install an aftermarket muffler silencer
Adding an aftermarket silencer muffler is a simple and effective way to get a noticeable quieter exhaust sound.
The system consists of an additional muffler and mounts that install to your OEM system as an auxiliary exhaust. Installation time is less than 10 minutes (as long as you don’t have to weld brackets), which means you can remove it or install it according to your needs if you want.
There are quite a few different brands out there that offer their take on this concept. They all work by the same principle; the exhaust has to pass through one extra muffler, stuffed with baffles and silencing materials.
One brand or model silencer may work well on some ATVs, but not so good on others. Make sure you read a review specifically for your bike before you decide on what type to get.
For example, some riders think the Kolpin Stealth (link to Amazon) is the best silencer available, while others report that it did not perform very well on their Polaris Sportsman XP 1000.
You’ll find model-specific mufflers that will bolt straight on to most major ATV brands. Or, if you don’t find one that’s made for your bike, you can opt for a universal model.
The universal models work just as well, but installation may require some modifications, and the final result may not look as stock as a custom muffler will.
What results you should expect varies a bit between the different brands available. But as a general rule, you should see an improvement of about 6-8db at idle. In some cases, you may see a reduction of as much as 10-12 dB when revving the engine at 2000RPM.
While 6-12db may not seem as much, it’s worth noting that an increase of 3 dB equals double the sound intensity. This means that a system putting out 99dB is 4 times more intense than a system that’s only emitting 93dB.
2. Install a spark arrestor
While the main purpose of spark arrestors is preventing forest fires, they also come with the added benefit of slightly reducing the sound output of your ATVs exhaust system.
The sound must pass through the steel mesh or baffles, breaking up the sound waves on their way out of the muffler.
However, do not expect drastic results from this simple tweak. You may expect results in the range of about 1-3dB reduction. On some ATVs, the difference with and without the arrestor is quite easy to notice just by listening.
Many stock exhaust systems already have a spark arrestor installed from when it was new. And if your bike is fitted with an aftermarket performance exhaust system or muffler, the spark arrestor may or may not have been included in the kit.
In some cases, you have to purchase it separately. It’s usually optional whether you want to install it or not.
The spark arrestor requires cleaning from time to time, so it has to be easily accessible. Installing a spark arrestor is therefore usually quite straight forward.
You may need to drill a hole or remove a couple of bolts, but that is usually about all it takes to install one. Just follow manufacturer’s directions or ask the dealer if you get stuck.
3. Repack your existing silencer
Inside some mufflers, you will find a fiberglass sound dampening material that helps to quiet the exhaust sound. I’ve seen this more often on aftermarket systems, but some stock system uses this technology as well.
Over time, this fiberglass material gets dirty, burns out and looses its dampening effect. So if your system is starting to have some age to it, you should consider removing the old stuffing and replace it with new.
All you need is some high temp silicone and some silencer repacking material that fits your muffler. Most manufacturers sell these as spare parts and it’ s recommend you stick with the OEM stuff.
The repacking process varies, but most manufacturers will provide proper instructions for four your specific silencer.
4. Packing the muffler with steel wool or fiberglass insulation
Some riders use steel wool or steel dish scrubs as dampening material inside their mufflers. This may result in some initial improvement, but it’s not an option that stands well over time.
It also comes with a significant fire hazard, which makes it an alternative I do not recommend.
What may happen is that the wool heats up until it gets glowing red hot. Then it gets tossed out of the exhaust as glowing red particles that can set dry leaves and such on fire.
Over time, oil and fuel may soak the steel wool. The glowing red particles may then cause the muffler to ignite from the inside.
When the steel wool burns out, it quickly loses it’s dampening effect as well. Not to mention potential rust issues.
Fiberglass handles the heat much better and will not glow from the exhaust heat. It is usually cheaper than steel wool as well.
If you are on a budget, fiberglass building insulation is a better alternative for stuffing material than steel wool because you won’t have the risk of incineration.
But the best option is always to get the OEM fiberglass mats. They are easier to install, won’t burn out as fast, and give the best dampening results.
5. Build a DIY extra muffler
If you want to keep your costs down and don’t care too much about the aesthetics of your system, consider building a DIY extra muffler made from a car muffler. It installs behind the stock system, just like the muffler silencers that are specifically made for ATVs.
Car mufflers are cheap and usually have a good dampening effect. Your best option would be to buy a small size model that fits your bike. You will also need a couple of 90-degree bends of the exhaust pipe in the correct diameter, and some flat steel to make a mounting bracket.
You will also need a welder or a lot of clamps to connect the different parts.
You should be able to make a system like this for half or two-thirds of the cost of a bolt-on system if you can live with the looks.
Be aware that back pressure and power loss may become issues if you choose a muffler that is too effective.
6. Fix any exhaust leaks
Even the smallest leak or crack can make your exhaust noticeably louder. It is common to experience shrill whistling noises when you apply throttle. Under deceleration, you may even get a backfire due to a change in backpressure.
The leak may be hard to spot, but start at the front and work your way backward.
Check all welds or joints between the different parts of the system extra carefully. The first few inches of pipe from the engine are usually most prone to leaks and cracks because of the big fluctuations in temperature.
Look for black zoot as it will be a sure indicator of a leak. Weld the leak or replace broken parts with new, and you should expect stock performance again.
7. Replace a damaged or rusted-out stock muffler
Like any other part on the ATV, the muffler wears out over time. And when it does, it also starts underperforming.
The most common wear on mufflers is that the sound dampening internals either rust away, burn out or come loose. When this happens, it will no longer dampen the exhaust sound as it’s supposed to. You may also get rattling sounds like a nice bonus.
If you wait long enough, you may find your muffler completely gutted out, with barely any sound dampening effect at all.
Not only will this give you a loud exhaust, but you may also run into issues caused by reduced backpressure.
The easiest way to fix a worn-out muffler is obviously just to get an OEM muffler that bolts straight on to the bike.
But if you want to save a few bucks and potentially get a quieter system there are a couple of DIY alternatives you may look into.
The first one is getting an aftermarket muffler silencer, intended to be installed at the end of your stock system.
Often you’ll find that these mufflers give a more silent system, even if you use it to replace the stock muffler. This option may, however, require some slight modification to make it fit.
Another cool option for silencing your bike on the cheap is replacing the stock muffler with a stock muffler from any Japanese racing motorcycle.
Owners of these bikes often replace their stock mufflers with aftermarket performance exhausts. You should be able to get your hands on the stock one at a very reasonable price or for free.
Modify it to fit your exhaust header pipe and mounts, and you should in most cases get a decent improvement in sound output.
Just remember that any time you create a DIY solution like this you are completely on your own if you run into any issues caused by a change in backpressure. We’ll look more into the potential risks involved further down this post.
8. Insert a quiet core insert in the muffler – dB killer
Some manufacturers of aftermarket exhaust systems offer quiet core inserts that can be fitted to make the exhaust quieter.
The design if these inserts vary, but usually consists of a baffled or perforated pipe that fits inside the muffler. These core inserts often come in combination with a spark arrestor and/or a downwards facing pipe for directing the sound down to the ground.
Not all manufacturers offer these types of inserts, commonly named dB-killers. But it’s definitely worth checking out if you already own an aftermarket muffler, or if you’re in the market for getting one.
It may be hard to visualize how the system will sound when you are in the process of purchasing the new exhaust.
So if your brand new system ends up sounding louder than you were expecting, it’s good to have the option of installing a simple insert to make it a few dB quieter.
The dB killer inserts usually install in just a matter of minutes.
9. DIY quiet baffle modification
If there are no bolt-on quiet core kits available for your muffler, consider making one on your own. You should be able to achieve just as good or even better results as with the store-bought kits.
What you should do is to get inexpensive universal baffle inserts and fit it to your existing exhaust system. These inserts come in a variety of shapes and sizes. Find one that fits the diameter of your exhaust pipe.
Depending on your bike’s piping design, you can make it fit by disconnecting a joint and tacking it or bolting it in place inside the pipe.
Alternatively, you can make an extension pipe at the rear of your muffler, that contains the baffle insert.
This is probably the best (cheapest and least ugly) budget solution for those looking to make their stock exhaust a bit more silent.
This modification should work fine on most bikes for low RPM trail riding or utility work. For racing applications, it is likely not the best option. Just make sure you restrict airflow too much so that you build up back pressure that can damage your engine.
More on that further down.
10. Make sure the sound is directed to the ground
This tip will not actually reduce the actual sound levels your system puts out.
But making sure the sound is being directed downward to the ground will have a big impact on how far the sound will reach after it has left your muffler.
With a straight muffler, the sound gets shot directly backward and can be heard from far away.
But if the sound gets directed straight down to the ground instead, the rough surface will act as an acoustic dampener. The sound waves ” break up”, effectively leaving them unable to reach as far.
To achieve this you simply install a sound direction pipe at the end of the muffler. A so-called down snout tip. This part is simply a small piece of bent pipe that changes the direction of exhaust flow downwards.
Most manufacturers offer this part as an option, or it may even be included when you buy the exhaust system. It should bolt-on in just minutes. And if you look around you will also find universal parts that may fit your exhaust.
As a final alternative, you can just buy a piece of 90degree exhaust pipe and weld it to the rear of your muffler.
11. Connect a coil of metal conduit
If you need to get your exhaust quiet in a hurry, this may be the method for you. Get about 6 feet of flexible metal conduit (made for electrical wires) and connect it to your muffler using a simple clamp. Coil it up and use some steel wire to keep it in place.
This will eliminate almost all exhaust sound, but be aware that you may be restricting exhaust flow too much.
Use this only when in a pinch and only for low RPM riding.
12. Ride gently when you can
This last tip is completely free.
Any time you find yourself in a place with a risk of disturbing others, simply drive gently until you are alone again. By backing off the throttle slightly you effectively reduce the exhaust sound to more manageable levels.
What option is best for you?
Now that you have a wide variety of methods to choose from, it’s time to decide which one that suits you the best.
Besides aspects such as cost, looks and the level of mechanical work involved in the installation you may find yourself asking questions such as;
- Is it safe for the engine?
- Will I lose engine power?
- What is best for my type of riding?
- Is it worth it?
Let’s have a look at how effective such modification will be for different riding scenarios, as well as some possible downside involved.
Silencing the exhaust for trail riding
The sound is widely recognized as the number one challenge by those who work hard to keep our riding trails open. A loud exhaust is also one of the major obstacles when looking to open up new trails to motorized recreation riding.
In later years, the problem has become even worse with large four-stroke engines entering the scene. These bikes tend to be a lot louder than the two strokes, especially when installing performance exhaust systems.
On one side you have ATV riders that just want to enjoy their trail rides. They feel that the occasional ATV passing by should be well within what others need to accept.
On the other side, you have those that feel loud engine sound is ruining their experience of being out enjoying the silence of nature.
In-between you find a great number of ATV enthusiasts with one leg on each side. These riders can simply not understand those riders that install screaming aftermarket exhaust on their big four-stroke machines just to achieve an almost unnoticeable power gain.
It’s not hard to understand why there is a conflict of interest here. And it really doesn’t matter which side you are on.
Riders that run loud aftermarket exhausts on open trails are contributing to heat up this conflict up to the boiling point. As a result, we see an increasing number of trails and riding areas being permanently closed.
Being able to ride on public ground is a privilege that is directly influenced by the majority. And all it takes to lose the right to ride on private grounds is one provoked landowner.
Less offended people equals more available riding grounds for us all to enjoy.
Another great benefit of having a silent exhaust on your trail machine is being able to communicate with your passenger without having to scram your lungs out. After longer rides, you get home feeling much less exhausted as well.
Quiet ATV performance exhaust for racing
It’s not only trails and open riding areas that are in danger of being permanently closed or heavily restricted because of sound issues. This is true for many race tracks as well.
Not all tracks are located out of reach from people’s homes and need to apply sound limitations so that they are allowed to stay open.
As a result of this, more and more manufacturers are now offering high-performance exhausts that keep sound output at reasonable levels as well. 96dB maximum sound level is becoming the norm. Some places even operate with lower limits.
Quiet ATV exhaust for hunting
If your goal with quieting the exhaust is to sneak past wild game completely unnoticed, you are most likely wasting your time and money. No matter how silent your exhaust is, most animals will pick you up long before you get within sight.
It is not only the exhaust which makes noise on your bike. Even when leaving exhaust sound out of the equation, the noise still present from your bike’s transmission, drive train, airbox, and mechanical engine noise is enough to make your ears ring.
Bikes with CVT transmissions are particularly noisy, where bikes with manual transmissions make for much better candidates as silent rides.
Even when riding an electric golf cart, the deer will hear you coming from far away. In addition, you have the smell from grease, oils, and exhaust that will blow your cover even if you were moving completely silent.
A quiet exhaust may allow you to drive closer to wildlife without scaring them away, leaving less disturbance in the hunting grounds. But they will still hear you coming.
Why bother using ATVs for hunting at all then?
As operators of loud forestry machinery and farming equipment will likely testify; the sound of their machines has never scared the deer away. How can this be?
The trick is not removing the sound and smell, but making the animal used to it!
All you have to do is take a few rides through the area in the last few weeks before the hunt begins.
Use the bike to check up on your deer stands. Use it to get to know your hunting ground by mapping out important spots such as water sources and food plots. Check your trail cameras.
Make all this a part of your season preparation routine and your riding will soon no longer be an abnormality that scares them.
On opening day you should be able to ride out with little chance of spooking them. In fact, walking in by foot will usually cause a lot more disturbance, than an ATV they are used to from before.
Can you hurt the engine because of increased backpressure?
When you make modifications to the exhaust system to make it quieter you will alter how the exhaust gasses flow through the system.
When you add a muffler you make it slightly harder for the exhaust to pass. Therefore it will require a bit more pressure to blow the same amount of air through the system in the same amount of time.
If you restrict air flow too much, backpressure may start building up inside the engine. You may experience issues like misfiring, stalling loss of power and the engine running too rich. None of which are likely to cause any damage to the engine.
But you may also experience the engine running too hot, which is not something you want.
As long as you stick to a reputable brand of mufflers that design and manufacture their mufflers for each specific ATV model, you should have little to worry about. These usually add very little back pressure.
But if you decide on one of the DIY alternatives, you are completely on your own if you mess up. Making such modifications will most likely void warranty, so be careful.
It’s always a good idea to have the jetting checked or to get a fuel programmer when doing modifications like described in this post. You want to make sure the fuel/air mixture is still within acceptable limits.
Aftermarket muffler manufacturers will often claim that you do not need to worry about the jetting, and I have no reason to doubt that they know what they are talking about. But if you want to be completely safe, it’s worth having looked after.
What about power loss?
More sound equals more power, right? This is not always the case anymore.
Both European and American manufacturers are now offering systems that are capable of keeping the sound output well below the recommended 96dB limit, without any power loss.
The tradeoff is usually that you get a physically larger and slightly heavier muffler. A small price to pay for keeping the trails open if you ask me.
And as long you stick to a reputable brand, you should have no noticeable loss of power by installing a muffler silencer neither. These systems add just about 2% of back pressure that will make very little impact on the engine performance.
In fact, you may actually experience a slight increase in bottom end power after installing the system.
Some of the DIY solutions, however, may cause some power loss, especially at higher RPMs. This makes such modifications best suited for hunting, Sunday rides or utility work.
If you’re into racing aftermarket systems are really your only good option.
It’s worth noting that if you ride at altitudes above 5000-6000 feet above sea level, you are advised to have the jetting adjusted for best performance. Some manufacturers will even offer specially designed systems made for high altitude riding, that will assure proper air flow and performance where the air gets thin.
Do ATV exhaust silencers work?
An exhaust silencer will reduce the sound level of your exhaust with up to 60%. It dampens the popping sound from engine-backfire and changes it to a lower pitch rumble. The actual sound reduction depends on the brand of silencer and ATV engine size.