MR12 is designed to make maximum power in four stroke dirt or street bikes with stock or mild modifications. VP’s best fuel yet for 4-stroke applications that can tolerate lower octane values. MR12 has met fuel rules for AMA Pro/Am, CCS, WERA, NMA, WORCS, SCORE and Best in the Desert as well as club level racing and more. As regulations are ever changing, we recommend checking with tech to be sure.