SAVE $500! Rates from 1.9% for 24 mons oac! CRF450X - Power at any RPM.Meet the reigning champ of Baja. Powerful 4-stroke 449 cc liquid-cooled four-valve Unicam engine is designed to produce power across a wide rpm band. Unicam valve train provides the lightweight of a compact single-cam design and the optimum combustion chamber shape for max power.