Flaming Gorge in southwest wyoming/utah will give you plenty of places to ride. Just pray there isn't any wind and watch out for the water temps, it doesn't get much past 70 by the end of August.
Glendo Reservoir in southeast wyoming is a lot like the Gorge, but warmer.
Let me know if you decide to take a trip there, I think it would be awesome if Wyoming gets some representation. If you have any other questions about anything else there, I'll be happy to help you out, I've spent most of my life there.