All AMA sound testing regulations are STRICTLY ENFORCED! At ADK MX, we will follow AMA rules every day that we are open. Quiet Cores must be installed on aftermarket systems and you must make sure the packing of any stock exhausts are fresh. Quieter machines are better for the sport, and the restrictions are getting tougher every year. Plus, your bike makes more power with more back pressure, anyways. Please help us with this. If we hear that it’s loud, we’ll test it. If it fails to comply, you will not be allowed to ride.