The Akrapovic Evolution systems with the ultra-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. 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 (96 dB).  Measurements of the Akrapovic EVOLUTION system on the SUZUKI RM-Z 250 (without muffler insert):  Power & Torque: The complete exhaust system offers increased power and torque throughout the rpm range. At 11300 rpm we measured 34.9 HP.