Crankcase, Oil Pump, 125cc 54mm ATVs & Dirtbikes

The crankcase and oil pump are critical to lubrication and structural support in 125cc 54mm ATVs and dirt bikes. When these components wear, crack, or lose pressure, engines can overheat or suffer premature damage. This collection includes replacement crankcase halves and oil pumps designed for Honda-type 125cc 54mm engines, helping restore proper sealing, lubrication, and long-term reliability.