Cypress CA, (June 27, 2008) - Yamaha Motor Corp. is pleased to announce that Sean Hamblin will be contesting the AMA Nationals from under the Yamaha Factory tent starting this weekend at Thunder Valley Motocross Park in Lakewood, Colorado.Riding a Factory prepared YZ450F, Sean will be teamed up with mechanic Dan Rambert."We couldn't be happier to have Sean join the Yamaha Family. He's done an amazing job on his 2008 YZ450F as a privateer and we are really looking forward to seeing what he is capable of on one of our race bikes", said Racing Division Manager, Keith McCarty."I'm really excited about this opportunity, and want to give special thanks to Andy Stacey and all my sponsors for helping me get everything together before Glen Helen. Without them, none of this would have ever happened. From here I'm looking forward to putting in some great results and turning this opportunity into a long term relationship", said Sean Hamblin.Sean will be riding under the Yamaha tent for Thunder Valley and Red Bud.