Set up a large maze in a field. However, there are no walls to the maze, just outlines on the ground.
The prank is in that the bikes are rigged with the same devices that prevent people from stealing shopping carts.
So essentially instead of hitting a wall in a regular maze, the wheels will just lock and the rider will be bucked off the front of the bike.
I see Knoxville, Bam, Steve-O, Ehren, and Wee-Man doing it. Perhaps Party Boy can be the prize in the middle of the maze