AMSOIL Synthetic Motorcycle Oils are specially formulated with premium synthetic base stocks and robust additive packages to provide tough lubricating protection in the most demanding operations. They are recommended for use in all four-cycle motorcycle and ATV engines, including those with wet clutch systems. AMSOIL Synthetic Motorcycle Oils are specially formulated with high levels of zinc and phosphorous for superior protection of cam lobes and other high pressure components. Testing shows that AMSOIL Synthetic Motorcycle Oils provide up to 80 percent better wear protection than other motorcycle oils.