Desc: Silver Anniversary Adelanto Grand Prix: Directed by Mitchell Greene. With Amanda Brewer. The Adelanto Grand Prix is the largest off road motorcycle grand prix in the United States, and features a race for everyone! Pee-Wees, Kids, Pros, Beginners, Young, Old alike! The Desert Vipers Motorcycle Club presents the Adelanto Grand Prix! Side Hacks, Vintage Bikes, Quads, Team Race and a carnival of friends, family, and fun of two full days of hard charging racing action!