2013 KAWASAKI KXa??450F, PROOF in Five Back-to-Back Titles The KX450F has been updated for 2013 to help continue its back-to-back string of recent championships. The string began with Monster Energy Kawasakis 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 Villopotos absolute domination of the Monster Energy Cup 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!