How To Check Motorcycle Exhaust Leak: (Causes, Signs & Fix)

This article will help you understand every essential aspect of a motorcycle exhaust leak and what are some signs/symptoms and causes behind it, and how to fix it properly to avoid damage to the exhaust system components.

To locate the exhaust leak, inspect the entire exhaust pipe from header to tale pipe/muffler by spraying soapy water or using tissue paper which will help you to identify leaks in the exhaust system by the formation of bubbles or tissue flapping due to the air being released through the leaks.

Checking the joints of the exhaust pipe such as where the muffler connects to the straight/back pipe or exhaust headers connecting to the exhaust port is where a majority of the times motorcycles have exhaust leaks.

You should fix the exhaust leak as soon as possible to avoid the concentration of heat from exhaust gases which will cause damage to the components of the exhaust system and engine.

But before we get started you should know that exhaust leak is a pretty common problem seen in motorcycles, but many people ignore it or aren’t aware of leaks in their motorcycle’s exhaust system.

By the end of this article, you will learn to identify an exhaust leak and what causes it, some early tale tell signs you should look out for, and finally how to fix your motorcycle’s exhaust leak.

How Do I Know If My Motorcycle Exhaust Is Leaking?

If your motorcycle has an exhaust leak, you will immediately hear a short intermittent popping/puffing sound, you will also experience loss of power, poor fuel economy, and overheating from the exhaust region.

The sound of the motorcycle exhaust changes when there is a leak, due to the exhaust gases/air being released through the leak it will create a puffing/hissing sound.

This puffing/hissing sound is created inside the exhaust pipe because of the build-up of high pressure from exhaust gases which are being released through the small leaks. 

Using a paper towel/tissue and hovering around the various joints of the exhaust system from headers to mufflers will help you identify an exhaust leak.

The tissue/paper towel will start to move or flap around the region of the exhaust where there is a leak due to the exhaust gases rather being released from those leaks instead of the end of that exhaust pipe.

Another quick way to know if your motorcycle exhaust is leaking is by spraying soapy water on the suspected region where there is an exhaust leak. You will see if there’s an exhaust leak, the soapy water will start to form bubbles around the leaked region once it comes in contact with exhaust gases/air.

Listening to the change of exhaust sound, spraying soapy water on a suspected leaked region, or hovering a paper towel over the leaks are the best way to quickly identify and know if your motorcycle exhaust is leaking.

Most Common Symptoms/Signs Of An Exhaust Leak?

Here are 8 common symptoms/signs which will you identify the severity of a motorcycle exhaust leak.

1. Distinct Ticking Noises

The ticking and tapping noises most people hear around the exhaust system are usually from a loose header bolt or bracket which vibrates when you idle or accelerate the motorcycle, creating that distinct ticking/tapping metallic sound.

2. Discoloration Of The Exhaust

If a motorcycle has an exhaust leak the exhaust gases rather than getting expelled through the pipe’s end will start to concentrate at the leaked region, which will increase the exhaust pipe’s temperature and cause premature oxidization at the leaked region.

Prolonged hot temperature of 392-1112 °F or 200-600 °C of the exhaust will cause discoloration which will turn the motorcycle’s exhaust color into blue, yellow, or purple.

The exhaust can get even hotter which will cause the exhaust pipe’s color to turn into blue, as known as blueing.

Keep in mind that when there is an exhaust leak in a motorcycle, discoloration will start to appear first at the leaked region of the exhaust pipe.

So here’s a quick super fun article on motorcycle exhaust changing color at different temperatures with a detailed color chart.

3. Loss Of Power

You will experience loss of power and the motorcycle will feel sluggish with poor acceleration due to high engine temperature and high amount of exhaust backpressure, which will cause inefficiency in the combustion process.

The exhaust gases will not to expelled from the exhaust system efficiently if there is an exhaust leak, hence resulting in poor performance of the motorcycle.

4. Loud Popping & Backfiring

An exhaust leak in the motorcycle can introduce an extra amount of atmospheric air into the exhaust, which can ignite some amount of unburned fuel inside the pipe resulting in a popping or loud backfiring sound.

The size of the exhaust leak will determine how loud the sound of popping/backfiring will be.

Here’s a quick article on How to fix motorcycle backfiring also known as engine backfiring. Also here’s another great article to avoid this problem developing into a serious Engine knocking condition and how to stop it.

5. Overheating Exhaust System

Exhaust systems are designed to carry the exhaust gases and expel them through the end of the exhaust pipe ( muffler/tail pipe).

An exhaust leak at the header or anywhere in between on the exhaust pipe will cause a concentration of hot exhaust gases on the leaked region rather than spreading throughout the whole pipe.

This will cause overheating of the exhaust system as the exhaust leak will cause inefficiency in ejecting all the hot exhaust gases from the exhaust pipe.

This overheating can cause damage to the internal components of the engine and exhaust system and will eventually lead to heavy amount of smoke coming out of the motorcycle’s exhaust. Here’s a quick helpful article on Why your motorcycle is smoking.

6. Louder Idle

A motorcycle with an exhaust leak will cause the pressurized exhaust gases to escape through the leak rather than through the end of the exhaust pipe.

This distribution in ejecting exhaust gases through the leak and the end of the exhaust pipe will cause the motorcycle to have a rough or louder idle.

The puffing/hissing sound will be muffled under the exhaust note but won’t be too hard to notice.

7. Poor Fuel Economy

Poor fuel economy is to be expected if there is an exhaust leak because the inefficiency of completely getting rid of the hot exhaust gases will cause the exhaust system to overheat and will transfer that heat toward the engine.

And an overheated engine and exhaust system are a perfect combination for poor fuel economy where the motorcycle will consume more fuel than it usually does.

8. Burning Gas Smell

During the combustion process, some amount of air/fuel mixture will remain unburned and will get expelled through the exhaust system.

An exhaust leak will cause the exhaust pipe to operate at high temperature than usual which will cause the unburned air/fuel mixture to get ignited and burned inside the exhaust system, hence this will cause a strong smell of burned gas from the exhaust system.

So these are the most common and obvious signs of a motorcycle exhaust leak that you will encounter if your motorcycle has it.

Now we will look into what are the causes of an exhaust leak in a motorcycle and how to prevent/avoid it.

Causes For A Motorcycle Exhaust Leak?

Direct damage to the motorcycle exhaust which can cause exhaust leak is either physical damage or wear over time (corrosion), apart from that loose fitting of exhaust parts such as headers, manifolds, mufflers, and catalytic converter.

So here are the 4 most common causes of a motorcycle exhaust leak majority of people can face.

1. Crack In Exhaust Pipe 

Damage can be caused to an exhaust pipe during any kind of accident where the exhaust pipe comes into direct high-impact collision with a hard surface.

Small cracks or bend near the header or other joints of the exhaust pipe should be thoroughly inspected.

2. Blown Head Gasket

A blown head gasket can be another cause behind an exhaust leak as it sits in between the cylinder head and the engine block which is closer to the exhaust port and the compromised seal will introduce atmospheric air into the exhaust and engine, so a blown head gasket can also cause an exhaust leak in a motorcycle.

A blown head gasket can cause some serious problems and damage to the engine if it’s not fixed properly, here’s a quick article on Everything you need to know about blown head gasket such as Fixing costs, Causes, Symptoms, & some useful Prevention Tips.

3. Loose Header Bolts Or Brackets

Rust, corrosion, or vibrations from riding a motorcycle over time may cause the bolts or brackets connecting the exhaust headers to the engine to become loose, this will obviously result in an exhaust leak.

So check for any corrosion buildup and clean it if necessary and tighten the header bolts/brackets to avoid an exhaust leak.

4. Overtime Wear/Corrosion Buildup

Overtime wear or corrosion buildup completely depends on how you maintain your motorcycle and clean it regularly as the condensation and corrosion buildup will weaken the surface of the exhaust and joints which can lead to cracks or holes resulting in an exhaust leak.

Is An Exhaust Leak Bad For My Motorcycle?

An exhaust leak is certainly bad for the motorcycle as it causes overheating of the engine & exhaust and prematurely oxidizes the surface and reducing its lifespan. 

You can expect poor performance and fuel economy if your motorcycle has an exhaust leak, as it intervenes with the process of exhaust scavenging and creates a high amount of backpressure in the exhaust system.

If the exhaust leak is not fixed early and properly it can later develop into other engine problems such as backfiring or sputtering and other host problems to the components of the engine and exhaust system.

How To Fix An Exhaust Leak?

A minor exhaust leak can be sealed or fixed with epoxy, stainless steel clamp, exhaust tape, or welding but for major leaks (big holes) it’s recommended to replace the exhaust system’s part where there’s a leak.

An exhaust pipe is made up of 3 to 4 parts such as headers/manifolds, catalytic converter, straight pipe/back pipe/bend pipe, and muffler. Exhaust leaks on any of these parts can be fixed or you might need replacement.

Motorcycle Exhaust Leak Fixing Cost? 

You can expect to spend $100-$300 on fixing a motorcycle exhaust leak with labor charges and the cost of replacing the complete exhaust system or the parts of it will range between $300 to $2000.

Minor leaks can be fixed in a professional garage but if the exhaust leak is major, then it will surely in a replacement of certain parts of the exhaust or the complete exhaust system depending on the size and damage of the exhaust leak.

The price of exhaust system parts or the whole system depends on the manufacturer and brand itself. 

Exhaust manufacturer brands such as Akrapovic Exhausts, Leo Vince Exhausts, Yoshimura Exhaust, Arrow Exhausts, or Vance & Hines Exhausts will provide top-quality exhaust system parts or complete systems depending on your needs.

Motorcycle Exhaust Leak FAQ