FMF Racing Turbinecore 2 Aluminum Muffler w/Stainless End Cap for Yamaha YZ250X 16-24FMF Turbinecore 2 Silencer Yamaha YZ250X The Turbine Core 2 features FMF's exclusive Turbine Dampening System, which allows for excellent exhaust flow through the spark arrestor canister. As with all FMF 2 stroke spark arrestor silencers, the Turbine Dampening System is built into the core, and is not removable. With its factory look, unrestricted power, and most importantly, the stamp of approval from the US Forest Service, the FMF Turbine Core 2