The 2006 season stands as an important demarcation line in Supercross history. The '06 campaign was the first one where all the major players chose to park their lightweight two-strokes in favor of thundering 450 thumpers. Nearly a decade after Doug Henry shocked the world in Las Vegas on his works YZM400F, the 250 two-stroke division became for all intent and purposes, the 450 four-stroke class. Leading this charge was Team Kawasaki's James Stewart, who quickly took the all-new KX450F to the se