Why are Motorbikes Allowed to Be So Loud?

Are you a motorbike enthusiast? Alternatively, do you like loud motorbikes with large mufflers? Or maybe your just at home hearing a bunch of bikes screaming up and down the road and looking for some info on whether its all legal for them to be that loud.

Either way, I’ll be explaining everything there s to know around this topic throughout this article today.

The majority of road users are willing to concede with the fact that the absurdly loud mufflers probably contribute to the reduced number of motorcycle incidents on the road. funny way to look at things, but its totally true!

On the flip side, it’s not proven the loudness reduces accidents on the road, although it is almost impossible not to hear their loud noises on the road. That said, it’s now time to dig into the mechanics and technical sides of motorbikes and why they’re so loud.

Where does the loudness of a motorbike come from?

The loudness of a motorbike is mainly due to the size of its muffler and length of the exhaust pipe. Technically, large mufflers provide little or no residence time for air and exhaust to slow down. Also, since the engine compartment is open to the air and atmosphere, you get a result of a loud sound. I happen to be a fan of motorbikes and have been riding for quite a long time. 

Besides, I’ve studied the criterion incorporated in the functionality of motorcycles and have even been able to take many of them apart and put them back together. Stick around, as I’ll be sharing my knowledge of motorcycles and why they are so loud.

What’s more, I’ll also get to review the regulations of motorbikes in the UK, why bikers love bikes as well as answer some of the most frequently asked questions.

Why are motorbikes allowed to be loud?

Before we get to a detailed insight on motorbikes, let’s first find out why they are allowed to distract motorist and other road users in the first place. Before I became a motorbike enthusiast, I noticed that whenever I drove my car down the road, it was very obvious that I could easily know that a motorcycle was either behind me or about to pass me.

It was loud enough to hear even while sitting in the car with my radio on high volume. Occasionally, I would ask myself questions such as why they are allowed to be that loud and why the traffic police did nothing about it.

After looking into it further, I managed to find that the existing maximum noise limit for motorcycles is quite high in comparison to that on the cars. Studies reveal that the first limit was set in June 1999. It was after motorbike manufacturers introduced a relative louder muffler on their new models.

The law had a more stringent 80dB (A), which only applied to new motorbikes with an engine capacity of over 175cc. 

Although the government has implemented some harsh regulations in an aim to control sales and replacement of mufflers and the construction standards of motorcycle silencers, there’s quite a huge number of aftermarket silencers in the market.

Besides, many manufacturers are coming up with modified designs capable of tweaking the exhaust system to suit your sound needs.

Regulations for the loudness of bikes in the UK

As mentioned earlier, although I was curious about the loudness of the motorbikes, I wasn’t sure there were strict rules against the behaviour. Surprisingly, I was right.

The current legal limit is 82-86 decibels, which is quite a loud noise.

Other rules apply to the tires, brake pads, number plates, daytime running lights, fluid leaks, and many more. I also noted that there is still no emission tests performed on the bikes. The decision on the bike’s noise levels is left to the tester to decide.

Notably, as long as my bike isn’t branded “not for road use” or “race use only,” even with an aftermarket exhaust, I might pass the test. Nonetheless, the noise emitted should not be in excess.

new vs old motorbikes

Are newer motorbikes quieter than older bikes?

The answer to this question will depend on the maintenance or even upgrade integrated into the bike. Without a doubt, we all love a taste of class and uniqueness. Of course, we all love it when we or something in our procession stands out. Today, there are fifty-year-old bikes capable of hitting overwhelming speeds. 

The only secret is to ensure the vehicle is roadworthy and that it meets all the required requirements every time the tests are performed. Although old models were quite loud, it’s possible to own a 1930s motorcycle with a BMW K1200GT engine. Even so, that doesn’t mean it will be quieter. The new versions boast quite a huge engine capacity, which also means that they are also loud.

Although the new motorcycle models feature bigger engine capacities, they are also equipped with advanced silencers capable of reducing the sounds to almost silent. As compared to the older bikes that feature less-developed silencers, new versions feature mufflers that have been tested and approved to have met the required noise capacity.

So, were the older bikes louder than the new ones? Yes, this is due to the fact that older versions do not meet the required noise capacity and, therefore, new versions are made to be less noisy.

Why do bikers love louder bikes?

Besides the fact that road users find loud vehicles to be quiet attractive, the majority of bikers tolerate loud noises simply because they love it. If you are not the type who is not comfortable riding loud motorbikes, chances are, you might find the environment to be quite uncomfortable.

Although there is no scientific explanation as to why some riders enjoy hearing how loud their motorbikes can be, the fact is, the noise will certainly attract people’s attention. I don’t mind attracting attention from other users and strongly believe that one of the key reasons why riders make their bikes so loud is so that they can show off their rides.

Besides, it’s also possible that the biggest reason why riders make their motorcycles to be so loud is for safety reasons. Indeed, without a doubt, it’s not possible to ignore a loud motorbike on the road unless you have a hearing disorder. Also, when a loud motorbike is around other vehicles on the road, they are likely to notice them and either overtake or be overtaken. 

Statistics from MIB reveal that unaware car drivers contribute to the biggest number of accidents involving motorbikes on the road. In case a vehicle and a motorcycle are involved in an accident, there is a high chance that the driver in the vehicle did not see the motorbike before the collision.

Frequently asked questions (FAQS)

What is the penalty for breaking the law on the maximum noise limit?

Penalties vary from one offence to the other. Normally, you will be given a verbal warning or a fixed penalty notice before being penalized for the offence. An offence regarding silencer or exhaust system is charged about $50, while a non-endorsable fixed penalty fee is about $60 for each offence committed. 

What is the current maximum permitted level for a motorcycle?

Currently, the maximum permitted noise level for any motorist in the UK is 82-86 decibels. Other countries have set the limit to 90 since the majority of motorcycle tires tend to be affected by wear and tear when they exceed the limit. 

Can you be penalized for modifying your exhaust?

Yes, the UK government has strict laws prohibiting the alteration of the required muffler standard. All motorcycles are required to go through the required tests to ensure that they are roadworthy. Besides, once they are approved, they are stamped with the British Standard reference. The stamp should read BS AU 193a: 1990/T3. Penalties can go to as high as $50 per offence.

Is it possible to tow a motorbike in your car?

Yes, it is possible to tow a motorbike in your car. However, besides finding the right trailer and installing the required hitches, you should know and understand the laws and safety precautions of towing a motorbike.

What do I need to do to reduce the noise on my bike?

It’s quite easy to regulate the amount of sound emitted by your muffler. The first thing to do is first to identify how much you want your muffler to sound and pick the right silencer. Notably, you should also put into consideration that the size of your muffler determines the sound it generates. Alternatively, you can consult your mechanic for professional advice.

Are aftermarket motorcycle exhausts UK road legal?

As long as the noise does not exceed the required noise limit, they are regarded as legal. Additionally, MOT testers are responsible for checking whether a motorbike is roadworthy and will often ignore the type of exhaust- as long as it passes the test. 

Do muffler’s size and design affect sound?

Yes, thanks to the current technological advancements, it’s possible to choose the kind of sound you prefer and how loud you want it to be. Big mufflers produce big sounds. Typically, the smaller your muffler, the quieter the sound. Mufflers are popular for tweaking the exhaust to suit the sound you want for your ride.


You should now know exactly why motorbikes are so loud, what causes them to be and why bikers love their sound too. If you’re on the other side of the fence, however, and absolutely hate why they are allowed to be so loud. Then be sure to check out the specs listed above to see whether your local bikers are in breach of the UK laws.

Picture of Leon Angus

Leon Angus

I love bikes. All types, but mainly motorbikes (or motorcycles for those in the U.S.). I also love cars, planes and boats too! I'm a qualified Motorsport Engineer that currently lives in the UK and drives trains for a living (weird combo, don't ask), I love to cook, into fitness and love to smell petrol in my spare time! A true petrol head at heart. This website is my path back into the motor industry and the place where I can shell fuel for fanatics along the way. Learn More about the mission here

1 thought on “Why are Motorbikes Allowed to Be So Loud?”

  1. One or two bikes around here are louder than all the other loud bikes. I mean explosively loud , so loud you dont think of a motorcycle but rather a terrorists bombs .
    Why havent I ever seen nor heard of a cop
    trying to stop this noise ? Are they not able or unwilling ? Has no one complained ?
    I dont need the extra squirts of adrenalin , especially at 1 in the morning .


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Picture of Leon Angus

Leon Angus

I love bikes. All types, but mainly motorbikes (or motorcycles for those in the U.S.). I also love cars, planes and boats too! I'm a qualified Motorsport Engineer that currently lives in the UK and drives trains for a living (weird combo, don't ask), I love to cook, into fitness and love to smell petrol in my spare time! A true petrol head at heart. This website is my path back into the motor industry and the place where I can shell fuel for fanatics along the way. Learn More about the mission here

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