Why Are Motorcycles So Loud?

Closeup of motorcycle parts

Motorcycles are mostly louder than any other type of vehicle because of the size of their muffler and the length of their exhaust pipes. These two parts of a motorcycle provide less to no residence time, and thus, the process of air exhaustion slows down. Also, as the engine of a motorcycle is not enclosed or open to the atmosphere, the air fails to stifle and thereby causes a loud sound. 

For most non-riders, the louder sound of a motorcycle is produced on purpose. However, if you are a motorbike enthusiast or have been riding one for quite a long time, you might know that it’s totally a misconception. Compared to cars or any other vehicles, motorbike mufflers are short and thus fail to suppress the sound in the engine. To understand the technicality, let’s dig deeper into the topic.

Why are motorcycles so loud compared to cars?

There are many factors that make motorcycles louder than other vehicles like cars and buses. Though there are a few exceptions, let’s discuss a detailed insight on the engineering of a motorbike. 

  • The exhaust line, gearbox, and engine of a motorcycle remain uncovered. As there is no shield around the powertrain, the piston going up and down produces noise that can be easily apprehended. However, in most cars, the powertrain, i.e., their gearboxes, exhaust lines, and engines remain completely covered and thus, the sound produced inside is deadend. 
  • In most luxury cars, noise-absorbing materials are used on different parts like the heat shield, cowl, hood under-shield, and firewall. These noise-absorbing substances are capable of reducing both exterior and interior noise. However, as these materials are expensive, they are not used in more economic vehicles. So in motorcycles, there are no such provisions. 
  • Let’s face the truth. Bikes are meant for thrill while cars are mainly for comfort. As most bikers want to feel the thrill of power, the engines are designed to meet their requirements. In cars, people look for a quiet environment and luxury, and thus, the engine of a car is designed to be quiet. Of course there are exceptions. Formula one cars or supercars are very loud to give the rider the impression of thrill. 
  • The major limitation to a bike engine is the length of its exhaust system. The exhaust system of a motorcycle is of a smaller dimension than a car. In most cars, the exhaust pipeline can be extended by elongating them in a zig-zag pattern. In most cars, the length of the exhaust pipe from the port to the end is around 10 to 15 feet whereas in motorcycles, these are around 3 feet long. Thus, the air rushing out of a motorcycle engine does not get much residence time to slow down and causes a loud noise. On the other hand, due to the long exhaust pipe in cars, the air coming out of the engine gets sufficient time to slow down and hence, doesn’t produce much noise. Apart from this, there’s another limitation of muffler design. The muffler in a motorcycle cannot be designed as in cars as it is visible and has limited space. The mufflers used in a motorcycle are smaller, usually only a few inches long. 

What types of motorcycles are the loudest?

Though most motorcycles make noise, there are a few that beat all. Here are the three types: 

The Harley-Davidsons

Motorcycles from the house The Harley-Davidsons sound really powerful. The secret behind their loud sound lies in its unique design. Most of the motorcycles of this brand come with V-Twin two-cylinder horizontal engines. In most cases, the pistons used in such engines are engineered to fire alternatively. This means that one piston will fire the crankshaft on each revolution. Apart from this, in most two-cylinder motorcycles, the pins of the crankshaft of such motorcycles are connected to both the pistons. However, the Harley-Davidsons crankshaft is designed with one pin that connects both the pistons. Additionally, their engines are mostly arranged in a V-shape and thus, prevent pistons to fire at intervals. This unique feature of the Harley-Davidsons makes them one of the loudest producing motorcycles. 

The Hayabusas

Motorcycles from The Hayabusas are designed for performance-driven riders. Known to be one of the fastest motorcycle-making brands, The Hayabusas not only gets you to the destination quickly but also produces a loud noise. The brand makes use of performance exhaust mufflers in their motorcycles. The performance exhaust used in these bikes is not only responsible for enhancing their performance but also exhaust sound. The motorcycles from The Hayabusas are so loud that one can hear them from a mile. 

The Hondas CG

The Honda CG is a cost-effective option for those who are looking for performance-driven motorcycles. This is one of the day-to-day work bikes that can cut off your traffic through their loud noise. These motorcycles come along with a coyote exhaust system that is highly critical of efficiency and power. The presence of a coyote exhaust pipe in Honda CG produces a loud noise. 

Can I do anything to make my motorcycle quieter?

There are a few riders who do not like loud noise. Those who want quieter rides can check their exhaust pipes that produce growling sounds. There are some ways in which a motorcycle owner can silence the exhaust pipes. 

  • Check if there are holes in your motorcycle’s exhaust system. This can be one of the major reasons behind the rumbling sound from your vehicle. If there are small holes caused by rust, sealing is an effective yet fast way out. However, to seal larger leaks, you might need epoxy, a patch, and other equipment. 
  • Replacing mufflers is yet another way to reduce the unbearable noise coming out of a motorcycle. Exhaust pipes and mufflers are easily available and quite affordable in the market. You can also upgrade standard bullet mufflers with better-performing ones like resonator mufflers to keep the noise low. These mufflers have fibreglass construction and thus have soundproofing abilities. Apart from resonators, dual-chamber models work great to cut down the noise. 
  • Covering the exhaust pipes with a good-quality wrap is an effective way to reduce vibration. The wraps are made of durable materials like titanium and thus, can bear the high temperature of the exhaust system. 
  • Many riders invest in an exhaust silencer to make the exhaust system quieter. Made of fibreglass, silencers narrow the hole of the exhaust pipe and act as a soundproof medium. However, while purchasing an exhaust silencer, check the diameter of your motorcycle’s exhaust pipe for easy and effective installation. 

Can I do anything to make my motorcycle louder?

Most motorcycle enthusiasts have a major obsession with loud exhaust pipes. So, if you are one of those who loves great-sounding bikes and wants to experience the thrill, there are ways to easily improve the sound of your motorcycle. 

  • Installing an aftermarket exhaust is a great way to make your bike sound louder. However, as aftermarket exhaust systems are add-ons, their installation completely depends upon the type of motorcycle and its in-built exhaust system. 
  • As exhaust systems help in the combustion of air and are responsible for muffle noise along with the performance of the motorcycle, it is important to consider tuning or changing your stock carb from time to time. Tuning or changing the stock crab is also very effective in improving the airflow and sound. 
  • Installing an aftermarket ignition can help you to transform the sound completely. If you are using a V-twin cruiser bike, you can go for spyke ignitions for better results. This add-on to your exhaust system reduces the strain while starting a bike and lets you experience improved power gains. 

About The Author

daniel and sarah on motorcycle

Want to Receive Exclusive Offers, Tips & Freebies