Yoshimura KX450F 19-23 / KX450X 21-23 RS-12 Stainless Full Exhaust, W/ Aluminum MufflerYoshimura KX450F 19 23 KX450X 21 23 RS 12 Stainless Full Exhaust, W Aluminum Muffler The current generation Kawasaki KX450 has won over a lot of riders with its balanced chassis and predictable power delivery. We felt theres still more on the table for improvement, enter our new RS 12. With countless hours of track and dyno testing, the KX450 responded well to our RS 12 with crisp and clean usable power that is up across the entire rpm spectrum. The