The final round of the Rockstar Energy Drink Motocross Nationals returns to RJ Motosport Park in Barrie, Sunday, August 14th. It’s the FINAL race of the National Motorcycle Motocross Race schedule and features the the best line up of world class motocross racers ever! You need to see this live! RJ Motosport Park in Barrie, Sunday, August 14th..Take Hwy 400 North to Forbes Rd., west to Old Second South then north to the track. Qualifiers start at 10, racing goes at noon!