Ya that sprocket doesn't look any bigger than mine and I'm running a 12 up front. Looks like he has moved everything out back radiator, fuel cell, probably the battery. Also looks like he has different A-Arms in the front than the rear which are probably lighter so the front end is looking way light and the rear is heavy which equals wheelieville. All I know is these thing are a blast to drive and reliable has hell in the dunes. I would like to try a bigger rear sprocket so I can do some wheelie's.