Kawasaki has wheeled out a factory KX450 with a prototype engine in the penultimate round of the All-Japan motocross championship today, and the team are keeping the bike behind screens until it gets wheeled out onto the circuit.

The new motor (left) is all hand-made with sand-cast cases that look very similar to the 2021 stock model (right). But you can clearly see there are differences to the ignition cover. It has a very large left-side radiator. The new engine looks very similar to the factory motor used by Romain Febvre and Clement Desalle in the MXGP series this year.

The Japanese event has qualifying today and the main race tomorrow. The track is the Kyushu circuit at Kumamoto, right next to the Honda factory where the CRF machines are made.

Photos by yahey772