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Why Are Motorcycles So Loud? (How To Make Yours Quieter)

Lots of people view motorcycles as being very loud, and quite a lot of them are. This leaves many wondering why it is that motorcycles are often so loud, and if it’s possible to make them quieter.

Motorcycles are so loud because they run using internal combustion engines, which make use of thousands of explosions per minute to power the bike. Apart from that, some bikes are louder than others, and this is often due to owners installing aftermarket parts or removing their mufflers.

5 ways to make your motorcycle quieter are:

  1. Install a quieter muffler
  2. Perform routine maintenance
  3. Install new tires
  4. Use a good helmet
  5. Invest in ear plugs

Having good mufflers can usually make your bike as quiet as it needs to be. There’s a bit more to it though, as there are different strategies you can take for making a motorcycle quieter, and more importantly, making sure your hearing is protected when riding. I’ll go through some of these below.

How Loud Are Motorcycles?

Motorcycle volume will really vary from bike to bike. However, when a motorcycle comes from the factory, it’s usually not very loud. What makes motorcycles loud, more often than not, is aftermarket modification.

Modified Mufflers

Many people will remove the standard mufflers and install aftermarket mufflers designed for louder noise or increased engine performance. Many riders may remove the exhaust system entirely and replace it with open pipes that don’t reduce noise at all.

These completely unmuffled bikes are one of the main reasons motorcycles have their noisy reputation. If you’ve ever ridden or been close at all to a motorcycle with no mufflers, you’ll know that they’re incredibly loud.

Constant Explosions

So, why are these unmuffled motorcycles so loud? Internal combustion engines do just that – combust. Every minute a motorcycle runs for, hundreds if not thousands of tiny explosions are happening, all inside your bike’s engine.

During combustion, a mixture of fuel and air is forced into a cylinder via a carburetor or a fuel injector. The piston compresses it, the spark plug ignites the mixture, and boom! An explosion occurs, and the source of power for your motorized bicycle is created. This process just simply creates a lot of noise.

Even with all of these explosions, if you have adequate mufflers and seals on your bike, this incredible noise can be mostly contained. However, if your mufflers have been changed, disabled, or are missing, the noise may be much louder.

Other Noises

As well as the noise that motorcycles themselves produce, the act of riding a motorcycle is a somewhat noisy thing to do. As you’re going along, you’ll be hearing the noise of the motorcycle, the wind, and any traffic or environmental noises.

When you’re in a modern car with modern sound deadening and seals, these outside noises are significantly reduced. Even the noise of the engine is mostly eliminated. Motorcycles, however, are much more exposed, and so you hear everything. The only ear protection most riders have is their helmet, and depending on the helmet, that may not be much at all.

Motorcycling Demographics

Another thing that doesn’t directly make motorcycles louder but can certainly contribute to it, is the demographic of people who ride them. While in some other countries, motorcycles are very utilitarian, and one of the most common forms of transportation in large cities, in most US regions, motorcycles are usually considered an enthusiast vehicle.

This means that it’s quite common in the US for someone to ride a motorcycle less for pragmatic reasons, and more because they want to ride. In other words, many riders ride because they want to, not because it’s cheaper or easier. This type of person is probably going to be more likely to modify their vehicle.

If a person only views a vehicle as a means of getting from A to B, they will be less likely to modify it or to care about it beyond its transportation-related usefulness. To them, it is a tool, and nothing more. Some people who ride see their bikes as tools, but many see them as much more than that, a motorized confidant, something to have fun with and take care of.

While for some riders this association may surface as preventative maintenance and diligent upkeep, for others it may surface in modification. To modify a motorcycle is to make it your own, to make it work in the ways that fit you best, not just what the manufacturer decided was best for the average rider.

Why Do People Like Loud Motorcycles?

Personalization & Fun

There are a few different reasons people like loud motorcycles. As stated before, personalization is a big thing in the motorcycling community, and most riders enjoy the sound that their engine makes, so they want to hear more of it.

Some engines also (subjectively) can sound much better when they’re less restricted by exhaust systems that have to meet EPA and DOT standards for noise levels and other such regulations. A motorcycle tuned for performance will probably sound a lot “better” than one tuned for noise reduction.

Enthusiast riders love the sensations of riding, and that includes the noise and vibration of the engine. While some riders prefer a quieter experience, some like to be fully immersed in the noise and rawness of a motorcycle. This often includes loud exhausts.

Safety

Another reason many riders prefer louder exhaust systems is the safety aspect. When you ride a motorcycle, visually you’re not very big. In comparison to a large truck or even just a car that takes up a whole lane of the road, motorcycles are truly tiny, and this makes them a natural target for people who aren’t paying attention.

Given this danger, when you ride a motorcycle, you want to be as noticeable as possible. Having good lighting, a brightly colored bike, and brightly colored gear can help you be seen and noticed as much as possible. Another thing that can help you stand out is a loud exhaust note.

If you’ve ever heard an electric motorcycle go past, you’ll know what I mean. Electric motorcycles represent the opposite end of this sonic spectrum. They’re almost silent. The only noises heard are the whirring of the motor and the spinning of the chain. If you weren’t actively paying attention, from a noise perspective, it would be almost impossible to notice one.

Louder Bikes May Be Safer Bikes

Loud bikes, however, are the opposite. Even while driving a car in traffic, you may hear a loud bike before you see it. This noise encourages drivers to pay attention, as they would with any loud noise heard while driving. When most drivers hear these loud exhausts, they look around and try to locate the source of this noise.

This reaction is exactly the one most riders want. Especially now, in the age of widespread mobile phone use, distracted driving is a huge danger for everyone, but motorcyclists especially. Any habit or choice that can encourage drivers to focus more on their surroundings can be seen as a positive. While it’s definitely not always the main reason people prefer loud motorcycles, it’s still relevant.

How Do People Make Their Motorcycles Louder?

The main way that people make their motorcycles louder is by altering the exhaust system. The exhaust is the main determinant for how loud your motorcycle will be and what it will sound like, so changing it is the most common reason that motorcycles sound different from their factory-released forms.

There is a whole successful business related to motorcycle aftermarket parts. Many brands produce sporty mufflers and other performance products for motorcycles. If you have any common new-ish motorcycle, you’ll probably have an easy time finding aftermarket mufflers online, in a range of styles and noise levels.

Custom Exhaust Systems

Many people will build custom exhaust systems for their motorcycles, whether designing and building them personally, or having a fabrication shop do it for them. This is also a common way that motorcycles are made much louder.

There are a few other ways people make bikes louder beyond muffler changes. Many people will change the air filters on their bike, whether changing only the filter element itself or converting the motorcycle to run on cone-style filters. Many will also change elements of the fuel system, such as installing an aftermarket carburetor. All of these things can affect how a motorcycle sounds.

Why Are Motorcycles Allowed To Be So Loud?

Motorcycle noise level laws will vary tremendously depending on your location. Within the US alone the laws around how loud a motorcycle (or any vehicle for that matter) can be are often varied in different states if not different counties.

The truth is, many motorcycles on the road are probably louder than they’re legally allowed to be. While some places will prosecute riders heavily for breaking sound restrictions, others won’t do so as much. Many riders just don’t care or are mostly able to avoid being ticketed for this infraction.

Older, Louder Bikes

Noise regulations also vary significantly depending on the year a given vehicle was produced. While there are noise regulations on every motorcycle sold in the US right now, this wasn’t always true. In general, old vehicles that are still on the road only have to meet the technical and safety requirements of the year they were produced, not the requirements of the current year.

These laws exist so that old vehicles may still be enjoyed in their original form. Without this type of law, any vintage vehicle would have to be retrofitted with airbags, different seat belts, and a list of other safety features. Not only would this be expensive, in many cases it just wouldn’t be possible given their older designs.

These laws also apply to sound limits for motorcycles. Old bikes born in a time without muffler requirements probably still don’t have those requirements. You’ll often see older bikes on the road that may be louder, but they’re most likely not breaking any laws.

5 Ways To Make Your Motorcycle Quieter

1. Install A Quieter Muffler

The most effective way to make your motorcycle quieter is by changing the muffler. Most bikes come from the factory with a muffler that is already pretty quiet, so the first step in this process is to determine if your bike has an aftermarket muffler.

Usually it won’t be hard to tell whether the muffler is original. Most factory mufflers won’t have text or logos on them, while many aftermarket mufflers will sport the logo of whichever brand produced them. If this method doesn’t yield results, try to find a picture of the original mufflers for your bike, and compare the two.

So, if you either have an aftermarket muffler that is too loud, or want your motorcycle to be quieter than what the stock muffler allows, you can install one or multiple mufflers to reduce the sound level. Most of the time, bikes are only loud because they no longer have the original muffler, or it’s damaged.

If you’re not comfortable with the process of replacing mufflers (especially if you’re changing the type or number of mufflers), seeking the help or advice of a professional is a good idea. Because mufflers affect how the engine runs, depending on how you modify them, you could be diminishing the performance or longevity of your engine, so keep this in mind whenever you think about changing them.

2. Perform Routine Maintenance

If your bike is especially noisy, and it’s not due to a loud exhaust, that noise could be indicative of mechanical issues that need to be addressed. The best way to remedy (and hopefully avoid) these noises and issues is by keeping your bike well taken care of.

Routine maintenance is the best way to have a trouble-free motorcycle. Most motorcycles have chains, so keep your chain well lubricated, as these can often make noise if not taken care of. Regular chain lubrication also lengthens the life of your sprockets, another part that can become noisy if not taken care of.

Shaft-driven motorcycles also occasionally require maintenance, although not as regularly. It’s usually a case of replacing a fluid or re-greasing a gear or two. Belt-driven motorcycles require less maintenance than the other two, but it’s still a good idea to check if your belt is still in good condition, as they will wear out eventually.

Routine oil-changes also promote longer life and less noise. Most motorcycles use the same oil for lubricating the engine as well as the clutch and transmission, so the small amount of oil inside your engine is responsible for quite a lot. Making sure this oil is replaced regularly is a good idea.

3. Install New Tires

Tires can have a huge effect on how much noise your motorcycle makes. Beyond the safety concerns, old tires often make a lot of road noise. The rubber becomes brittle and sometimes misshapen after many years of use, or even just sitting not being used, and can vibrate and hum at higher speeds.

Replacing your old rubber will give you a much smoother ride, less road noise, more grip, and an overall better experience. Tires also reach a point where they become unsafe to use, so replacing old tires is important to do regardless of noise issues!

4. Use A Good Helmet

While this one doesn’t actually make your motorcycle quieter, it certainly could make it quieter for you as the rider. For many riders, a helmet is all that protects their ears from the noise of their motorcycle, as well as wind noise, and any other traffic noises.

Cheaper helmets often have less soundproofing, or sound reduction that doesn’t work as well. It really does make a huge difference what helmet you have. You may find that a nice helmet with good ear protection brings your motorcycle’s noise down to a level that doesn’t bother you at all.

The amount of noise we hear when riding can really affect us, especially on long trips. Having a helmet that blocks noise is not just a concern for comfort but also safety. If noise is reduced, it’s much easier to focus for long periods of time without running out of energy, and you’ll keep your ears in good condition too.

5. Invest In Ear Plugs

Another non-motorcycle thing to consider is purchasing a set of ear plugs. While not all motorcycle riders like riding with these, some swear by them and won’t get on their bike without putting them in.

There are many different brands and varieties of ear plugs available, ranging in size, style, and sound cancellation level. You should be able to find an earplug that works for you no matter how much or little noise reduction you want.

Some riders don’t like these, as they often feel that ear plugs eliminate potentially important road noises, such as the noises the motorcycle makes, as well as horns or information from other drivers. It’s not very expensive to try them out, though, so it’s worth considering, but bear in mind this safety consideration first.

Final Thoughts

Motorcycles aren’t always louder than any other vehicle with an internal combustion engine. You can limit this noise by making sure you have adequate mufflers on your bike. Many motorcycles are simply louder because they don’t have sufficient mufflers, or any mufflers at all.