The AMSOIL 100% Synthetic 4T Performance 20W-50 is a special motorcycle engine oil, which is developed for V-Twin engines and high power sport bikes. Both of these motorcycle types need an oil with the best heat management, wear protection and performance delivery. The AMSOIL 100% Synthetic 4T Performance 20W-50 provides smooth shifting, as it protects the clutch and increases the lifetime of it greatly.