At one time, two-stroke dirt bikes dominated the motocross and supercross racing scene. That is until about 20 years ago, when the two-stroke engine disappeared from motocross above the youth levels.

Take the transition from 2-stroke dirt bikes to the 4-stroke machines we see on the track today, for example. The first ...

the company looked for opportunities to expand its horizons and saw opportunity after the introduction of Yamaha's first 400cc 4-stroke bike, a groundbreaking model for dirt bikes in 1997.