For motorcycle modifications, different people like different modification styles. But most of the modified parts are similar. The parts that can be modified are simple sticker pull, in addition to damping, brake horns, upper pumps, piping, headlights, and exhaust pipes have become the most popular structures that people like to modify. Today we will talk about the knowledge of exhaust modification, which interested motorcycle enthusiasts can continue to see.
Types of exhaust pipes
Exhaust pipe from the structure is usually divided into back pressure pipe, straight pipe, and diffusion pipe three, the main difference in the internal structure design. From the exhaust tail section, the back pressure pipe is mainly to maintain the overall back pressure resistance, there are multiple cross partitions inside the pipe, and this design can reduce noise. Generally, most of the original exhaust pipes use this structure, because to meet the requirements of exhaust emission regulations. The straight-through pipe is designed to reduce the exhaust resistance by removing the internal partition so that the exhaust gas can be discharged more quickly, but at the same time, the noise is very high. Most of the general market for street-fried modifications so.
As for the diffusion tube, the structure is more special. There is no obvious exit design, but the use of the tail end of the gap between the diffuser to discharge exhaust gas, through the number of changes in the diffuser to adjust the exhaust back pressure resistance.
Why do motorcycle exhaust systems have square boxes
Many large-displacement motorcycles nowadays, to comply with increasingly stringent environmental regulations, will make their exhaust pipes longer and longer to add more spacers. However, when the exhaust pipe is too long it adds weight and changes the vehicle's center of gravity. The lightweight, center of gravity is the focus of modern motorcycle design, so the bulkhead will be moved from the rear end to the middle section to reduce the pressure on the rear section so that it will be connected to the catalytic converter at the bottom of the vehicle, which also allows the vehicle to have a more center of gravity.
The function of the catalytic converter
Simply put, it is to reduce pollution by converting the exhaust gases produced by the engine into harmless gases for discharge. This is achieved because the catalytic converter has many precious metals as catalysts. However, catalytic converters are afraid of lead, which can adhere to the surface of precious metals and lead to poor catalytic effect or failure. Therefore, it is better to use unleaded gasoline for motorcycles and avoid adding some strange fuel additives. Moreover, the catalytic converter works at high temperatures, so it is usually designed in the head or middle section of the tailpipe.
The difference between a tail section and a full section Simply put, the tail section occupies the largest volume and weight of the entire exhaust system. Only the tail section does not need computer tuning, can quickly reduce weight, and through the internal pipe, diameter changes will change the sound. And change the full section of the exhaust, you need computer tuning, to increase the power output. Of course, changing the tail section can also increase the power, but not as obvious as the full section. The price of the full section will be higher than the tail section.
The role of the tail-end valve Part of the original tailpipe at the end with valve control, mainly through the valve to control the back pressure of the speed area, so that the engine output achieves the best efficiency. And even if the increase in engine power can also ensure compliance with emissions regulations, while also using the valve to control the volume of exhaust noise.
How to change the sound of the exhaust pipe
First of all, the sound of the exhaust pipe is divided into loudness, tone, and sound quality. Loudness is the volume size, the tone is high and low, and sound quality is the sound quality. This mainly depends on personal preferences, each person's preferences are different. Motorcycle exhaust sounds size and displacement and muffling are related, while the tone is related to the engine speed. The sound quality is related to the mechanical structure and subsequent adjustments. To be precise, we try to change the sound by changing the exhaust, mainly by removing the anechoic sound to improve the loudness, or by changing the tail section (caliber and internal structure changes) to cause changes in sound quality.
What are the key points of modifying the exhaust pipe
First of all, the larger the diameter of the exhaust pipe, the greater the horsepower. High speed needs fast exhaust, large diameter is effective. And low speed needs to be reduced to maintain the continuity of the pipe. So the exhaust pipe is not the larger the caliber, the greater the power and horsepower.
Second, the material is divided into iron, stainless steel, carbon fiber, and titanium alloy. Iron pipe is cheap but has insufficient heat dissipation, stainless steel is more durable than iron pipe and has good thermal conductivity, it is moderately priced, and is the most common exhaust material. Carbon fiber and titanium alloy can effectively reduce the weight, the anti-hot effect will also be better. Carbon fiber is mainly used in the tail section of the exhaust pipe because of the material, while titanium exhaust pipe is too expensive, most of them are also used in the tail section, and the front section is made of stainless steel.
Finally, to significantly improve the power to change the full section, but need computer tuning. This requires a professional tuner or store. Generally speaking, modifying the rear end can increase the power a little, and will change the sound, mainly to make the vehicle lighter and change the center of gravity compared to the original factory.