The Honda Stunner is a motorcycle model that was available in certain markets. It is important to use the engine oil recommended by the manufacturer to ensure proper performance and protection of the engine. The best engine oil for the Honda Stunner would be the one specified in the owner's manual or recommended by Honda.
Honda typically recommends using their own brand of engine oil or oils that meet certain specifications. These specifications are often denoted by codes such as API (American Petroleum Institute) or JASO (Japanese Automotive Standards Organization). For example, you might find recommendations for oils meeting API SJ, SL, SM, or SN specifications, or JASO MA or MA2 specifications.
To determine the specific oil recommended for the Honda Stunner, I would suggest referring to the owner's manual or contacting a Honda dealership or authorized service center. They will have the most accurate and up-to-date information on the recommended engine oil for your specific motorcycle model.