Gran-Am Motocross ParkMay 19 1974Gran-Am Motocross ParkHamersville, OH250MX Results 500MX Results Results Home 1974 Results Gran-Am Motocross Park Live & On-Demand Learn More * all times Check back for a full broadcast schedule closer to the race. 1974500MXFull Results JimWeinert1st JohnUntiedt2nd GarySemics3rd 1974250MXFull Results PierreKarsmakers1st RichThorwaldson2nd JohnFranklin3rd