The greatest horse racing movie ever made was EASY MONEY, starring Rodney Dangerfield, and Joe Pesci. Pesci jumping over the fence, yanking Bill Popfinger ( I believe ) off the bike, and trying to beat the crap out of him, was the most realistic glimpse of harness racing, ever. Drivers no longer have to fear of this, as nobody goes to the track anymore.
Sincerely, Silent One