At the heart of the RS 125 is a sophisticated single-cylinder two-stroke, liquid-cooled engine, based on the same race-proven technology that has resulted in a continuous string of competition victories for Aprilia Racing. Able to reach triple digit speeds, the powerplant is packed with technical advancements including a crankcase reed valve intake, anti-vibration balancer shaft and an automatic fuel-oil mixing system. A robust 6-speed transmission delivers the power to the rear wheel with ratios designed to suit a variety of race track configurations. The RS 125 is fitted with high-performance, race-style, upside-down front forks and a hydraulic rear monoshock mounted in a rising rate linkage, designed to work in concert to deliver the highest degree of race track compliance.