The RS-4 not only increases power and is light, but it also has a lower centralized mass coefficient to provide better handling. Additionally, an overall improvement to the power delivery was also realized. The RS-4 is pentagonal shaped muffler that features a carbon fiber cone end cap, two staged stepped baffle and striking good looks. The RS-4 muffler features a new front cap design that functions as a polyresonant chamber. This design makes for a quieter muffler with improved mid to top end power.