Why some motorcycle exhaust sound so nice

Some riders play motorcycles, in addition to the kind of gallop pleasure, the sound of the exhaust is also one of the focus of attention. Often a riders asked me how to make their car sound better to listen to.
Like what kind of voice, in fact, people are different, some people like the kind of continuous roar of multi-cylinder machine, and some people like the kind of crisp sound of a single cylinder two red. Different models, the sound is different, then, what is the decision of the motorcycle exhaust sound?

First, the engine exhaust several key points and their role

Exhaust manifold Is the closest part of the engine, it is connected with the exhaust hole of each cylinder, this mainly for multi-cylinder car.
2. Three-way catalytic converter. After the exhaust manifold, responsible for the conversion of harmful gases, most carburetor motorcycles do not have this.
The middle of the exhaust. The main role is to reduce resonance and reduce noise.
4. exhaust tail section. Is often seen that the thickest part, responsible for silencing.

Second, the impact of exhaust sound one of the elements back pressure

Simply put, the engine exhaust gas through the pipeline in the process of encountering the resistance, is "back pressure." Back pressure, discharge resistance is large, the exhaust efficiency is low, suitable for medium and low speed under the force; back pressure is small, the discharge resistance is small, the exhaust efficiency is high, suitable for high speed under the force.

What determines the size of the "back pressure"?

1. Smoothness of the inner wall of the exhaust pipe;
2. The degree of bending of the exhaust pipe;
3. The complexity of the structure in the exhaust pipe.
These will determine the size of the back pressure, and our motorcycle exhaust are also by changing the above variables, to shape the different character of the exhaust.

Third, the impact of exhaust sound elements of the two materials

Material is also able to affect the exhaust pipe sound factors. Now can see the exhaust pipe, there are ordinary steel exhaust pipe, stainless steel exhaust pipe and titanium alloy exhaust pipe.