I was browsing the internet and found this article where a Grizzly 660 actually ran in a ATV race against TRX450's and yzf450's ect...and WON!!! he beat them all!! LOL!!!!
http://www.biker.force9.co.uk/feature_report_pend2004fe22trelow.htm
http://www.biker.force9.co.uk/feature_report_pend2004fe22trelow.htm