The specific regulations regarding modified exhaust systems, including loud and noisy silencers, can vary from country to country and even within different regions or states. Therefore, it's important to note that my response is based on a general understanding and may not reflect the specific regulations in your location.
In many countries, including India where the Bullet/Enfield motorcycles are popular, there are regulations in place regarding vehicle modifications and noise pollution. These regulations often cover the modification of exhaust systems and the acceptable noise levels for vehicles.
If a motorcycle owner modifies their Bullet/Enfield bike with a loud and noisy silencer that exceeds the permissible noise limits, they may be subject to penalties or fines. Law enforcement agencies and transportation authorities are responsible for enforcing these regulations, and they may conduct checks and issue challans (traffic violation tickets) to individuals who violate the noise regulations.
It's important for motorcycle owners to adhere to the local regulations and ensure that any modifications made to their bikes, including the exhaust system, comply with the legal requirements. This typically involves using exhaust systems that are approved by the relevant authorities and designed to meet noise and emission standards.
To have accurate information regarding the specific regulations in your location, it is advisable to consult the local transportation authority, traffic police, or refer to the official transportation regulations and guidelines provided by the governing body responsible for motor vehicle regulations in your area.