Im right here in New Iberia, LA. We've been to the dunes quite a few times, usually for the big events. You ever been to wiggins mississippi? If not they're having a huge event, Clash of the Titans, being held there this year, March 12th, 13th, & 14th. You should come out, there's a groomed 300' drag strip and tons of dunes and trails to ride on. O, and id go with the 9 extremes, 21" best for your setup, imo.