But there is more to Harley exhaust systems than gleaming chrome and bestial growls. Understanding the function of your exhaust lets you choose the best one for your bike.

Dealing with Emissions

The full Harley exhaust is designed to deal with the output of an engine, dealing with environmental, aesthetic, and legal issues.

The converter is designed to change harmful chemicals in the emissions into something less damaging to the environment. It uses a catalyst to convert dangerous gasses, including carbon monoxide and unburned fuel into carbon dioxide, water vapor, and other innocuous compounds. Reducing harmful emissions is not only environmentally friendly - it is also required by the EPA.

The muffler control sound and sparks. Although many Harley owners like the roar of their engine, many communities have noise ordinances that limit how loud your bike can be. Mufflers don't necessarily just suppress sound. They can also be used to control sound to get the noise you want from your bike.

Performance Enhancement

Your Harley exhaust system has a strong effect on engine performance and power. A clogged or poorly designed system restricts the flow of exhaust and reduces engine efficiency. Consider a path from the gas tank through the engine to the exhaust. If any part of that path is restricted, the whole system slows down and that means less fuel to your engine and less power.

Most people understand that a clog in the fuel line reduces power but may not realize that a clogged exhaust can do the same. Clogs aren't the only problem. An inefficient Harley exhaust restricts the flow from the engine and that creates a backup which cuts performance. Well designed systems with smooth curves rather than sharp corners allow the exhaust to vent more easily and the engine to run better.

High vs. Low Mounting

Where you put your exhaust, a high vs. a low position, will generally be determined by the bike's use. High-mounted Harley exhausts are used for bikes that will be used on trails and off-road. These bikes get a lot of dirt and water coming their way and the pipes are mounted high to keep these contaminants from getting into the exhaust and clogging it.

The problem with high-mounted exhausts is that they aren't very passenger friendly. Street bikes are more likely to carry passengers and don't need the protection of high mounts. These motorcycles are more likely to opt for low-mounted exhaust systems.

Choosing the right exhaust system is key to both the look and performance of your bike so consider all of your needs before making your choice.