Brand New! Yoshimura RS-4 Slip-On Exhaust - 2024 Yamaha YZ250F While other exhaust brands just carried over their Yamaha YZ250F offerings to include 2024 model, on the dyno and track, the new YZ told us there was more on the table. So our R&D team went to work to optimize the new Yamaha. Revised for the 2024 is our RS-4 slip-on for the new YZ250F. Adding 1% max HP and 1.2% max torque, the RS-4 slip on is a great option for adding some power. RS-4 also has the ability to add a spark arrestor for off-road adventures. Yoshimura's RS-4 system is proudly designed, developed and manufactured in Chino, California. Pentagonal-shaped sleeve Front muffler cap functions as a polyresonant chamber which helps reduce noise Two-stage stepped baffle Carbon fiber end-cap Stainless steel tail-pipe