The Akrapovic Racing and Evolution systems with the modern HEXAGONAL muffler look great on the RMZ. And since these systems are designed for riders who expect maximum performance from their exhaust systems, the visual enhancement is matched by the performance increase. New for 2008 is additional chamber that helps to reduce noise emission and provides better power and torque at low rpm range. They are designed for two markets: for the European and non-US other markets they come with a built-in noise damper, and for the American market they come with an approved spark arrester.