EBC CX Series – Hard Drive for Motocross. The material used for the new CX-discs is full, heat-treated stainless steel with high friction effect. With the improvement of the friction effect, the braking force is further increased. The design ensures excellent optics for various motocross models. The so-called “V-notch” in the profile object of the brake discs helps to clean the brake disc. Another goal is weight savings. The fewer holes there are, the better the braking performance on wet surfaces and the less wear on the brake disc.