Genuine rear sizes allow a smoother transition from OE tire geometry to professional tires and helps the rider skip some of the setup variables a professional racer is required to manage
Performance at the first corner: Extremely quick warm-up and allow riders to approach a track without worrying about tire temperature into the first corner
Single Ply, pure radial structure: Having a tire structure that best resembles the OE one assists the most in having to find the correct bike set-up to maximize your track day experience