I bet he let off the gas and with that huge 4 stroke motor had so much torque that when the front tires came down it acted like having the front brakes on. Anyone that rides a big 4 stroke knows that if you let off the gas the bike slows down really quick. Now you have a huge motor and a 4X4 making the effects of chopping the throttle that much worse and you get what the pics show. It's sort of like trying to jump a 4 stroke but before you take off you let off the gas. I bet you nose dive and wreck.