Field tests were conducted in a variety of Japanese two-cycle gasoline engines, comparing several lubricating oil additive types in motorcycle and small truck service. Three popular types of two-cycle additives were tested, the non-metallic amide and imide types, and the metallic sulfonate type. These field studies showed that (1) at moderate-to-high additive treatments, the amide type gave superior performance followed by the imide type, and then the sulfonate type; (2) at lower additive treatment, the imide type gave superior performance, followed by the sulfonate type, and then the amide type.
