The 2019 model marks the beginning of Kawasaki’s newest generation of what was previously known as the KX450F. However, the Japanese manufacturer has dropped the “F” from its naming convention as it only produces four-stroke motocross bikes. In addition to the chassis and suspension, the engine on the KX450 is completely new, and features electric start and a hydraulic clutch. The valve train uses designs from Kawasaki’s World Superbike engineers with finger-follower actuation, larger-diameter titanium valves, and more aggressive cam profiles. Additional new components are the 44mm throttle body, downdraft-style intake routing, engine cases, bridged-box piston, header pipe, shift drum, and shift fork.