2013 Kawasaki KX450F, PROOF in Five Back-to-Back TitlesThe KXa??450F has been updated for 2013 to help continue its back-to-back string of recent championships. The string began with Monster EnergyA? Kawasakia??s Ryan Villopoto winning both the 2011 Supercross and 2011 Motocross titles, followed by leading the U.S. team to an overall victory at the Motocross of Nations, then Villopotoa??s absolute domination of the Monster Energy Cup a?? which also earned him the Monster Million. Last but not least, Villopoto recently defended his Supercross title by winning the 2012 championship on his KX450F!