This part of ISO 6743 establishes the detailed classification, in tabular form, of engine lubricating oils for use in the following internal combustion engines: a) two-stroke cycle, spark-ignition gasoline engines that employ a crankcase scavenging system and are used in transportation, leisure and utility applications, such as motorcycles, snowmobiles, chainsaws (hereinafter referred to as two-stroke engine oils); b) four-stroke cycle, spark-ignition gasoline engines that employ a common sump containing the lubricant for both the engine and the drive train/starter/transmission of motorcycles, motor scooters, all-terrain vehicles (ATVs) and related equipment (hereinafter referred to as four-stroke engine oils). Outboard motor and marine engine applications are described in Annex A. It is expected that this part of ISO 6743 be read in conjunction with ISO 6743-99 [1].