South African rider wins 2006 AMA Supercross Lites West. Grant Langston won yet another AMA racing title in thrilling fashion. The South African took the AMA Supercross Lites West title this past Saturday at Qwest Field in Seattle, by winning the final race of the series aboard his Monster Energy Drink/Pro Circuit Kawasaki. Langston was four points down to Honda’s Andrew Short coming into Seattle, but his victory, combined with a disappointing eighth-place finish for Short, helped Langston win his fourth AMA championship.