McNeil, 32, was practicing in the midway area outside the frontstretch grandstands before the area was open on Sunday morning. He was taken by CareFlight to a local hospital, where he was pronounced dead.
McNeil, who was known as "Jumpin' Jimmy," had competed in Freestyle Motocross for 11 years, and finished fourth overall in FMX at the X Games in 2006. He had been part of the Boost Mobile FMX team for nine years.
In Freestyle Motocross, riders are scored by judges based on a series of jumps and tricks. The most famous FMX rider may be Travis Pastrana, who is transitioning to NASCAR, or Carey Hart, who is married to the singer Pink.
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