Unveiled in late 1989 as a new 1990 model, the MC21 took the 2-stroke world bu storm, and completely re-wrote the rule book on how.a 250 2-stroke should be built. The craftsmanship was superb, and the new features were groundbreaking! The mC21 now utilized PGM-III ECU (also being utilized in GP250 by official HRC Factory nSR’s). Coupled to throttle position & gear position sensors, the PGM-Iii controls controls the timing of the RC Valves, air correctors and ignition advance to give outstanding low end tractability. The PGM-III features a true 3D ignition and a different map for each cylinder.
In keeping with their racer for the road image, the famous Gull-Arm rear swinger was copied from the factory NSR250 of Luca Cadalora, as well as the frame design.