Developed by the Team Graves Yamaha supermoto team for use on Yamaha supermoto race bikes. This piston is compatible with oversize valves, higher lift cams and incorporate an ?X? style forging for additional strength, durability and weight reduction. These pistons represent the highest quality and are engineered for maximum power. Includes new cir clips and wrist pin.  This piston is designed to run on race fuel only (i.e. VP Racing Fuel U4 or MR9)