300 CC Dirt Bikes, 250 CC Dirt Bikes | Pit Bikes 125 CC, 150 CC | Best Automatic Mini DirtBikes: Shop the best mini dirtbikes and pit bikes for sale at MotoBuys! Choose from 49cc, 125cc motorcycles, 150cc, 250cc, or 450cc with strong frames. Our automatic and pocket bikes are made for rugged roads and daring adults.