Designed to be used with OEM stock head pipes or Pro Circuit head pipes Ultra-responsive performance Incredible horsepower gains when compared to stock Developed to increase the horsepower and torque throughout the power curve Aluminum/stainless construction for reduced weight and increased durability Strong mounting bracket(s) for increased durability Designed for easy disassembly and re-packing when needed Removable USFS approved spark arrestor 2005-2015 Honda CRF450X - - 2005 Honda CRF450R - - Fitment Disclosure This quick reference fitment information is provided to direct you to our catalog information and the manufacturer's information. Consult manufacturer publication(s) and/or website(s) for specific fitment and application information and other important information. This fitment information is based upon the stock version of the motorcycle or unit referenced and any accessory added or other modification could invalidate the quick reference information provided.