Description: Not all exhaust are created equal.

When it comes to functionality and aesthetics, the exhaust system is undoubtedly the most
important part of your motorcycle. It’ll announce your presence and is a major aesthetic component to your bike’s appearance.

Any exhaust you add must be able to deliver self-sufficient power and aesthetic appeal.

In other words, it has to work well, it should probably be pretty loud, and it has to look badass.
Before purchasing a new exhaust system, there are two main components to consider: Length
and Diameter. These two elements have an impact on performance. We’ll dig into them here.

By the end, you should be equipped to start shopping for the exhaust that suits you best.

Muffler Diameter

One element that can affect performance is the diameter of your exhaust muffler.

For your bike to operate at its full potential, the pipes diameter is crucial. Too narrow, and exhaust back pressure can increase flow resistance, decrease pumping, and increased pressure on the piston. Similar to this, exhaust with a large diameter will reduce back pressure decreasing velocity. A smaller diameter pipe will give you a snappier sound (high frequency) and a larger diameter pipe will give you a deeper sound (low frequency).

Overall Length

The engine’s capacity to control the oil, air, and other byproducts after each exhaust cycle are
related to the overall length of the exhaust.
Why?
In order to remove any excess, the system uses both inertia and wave scavenging intake
pressure.
The scavenging, or pipe length, aids in generating positive and negative pressure from the
combustion and the cylinders to allow gasses and residue to exit the system.

Translation: Lower scavenging = less horsepower

The negative pressure will lower the valve’s pressure and help regulate the combustion gasses
if the pipe is stretched to better fit the engine.

Note: changing the internals of your motor changes this equation.