I'd be careful if contemplating the use of any motorcycle oils in an automobile engine. Most motorcycle oils are intended to be used in a wet clutch environment (the engine crankcase and the tranny/clutch share the same
oil) and therefore lack some of the anti-friction additives found in moden automobile oils. You don't want to use regular car-type
oil in a bike because it can mess up the clutch, so you probably had better not use bike
oil in a car. There are many more additives in a bottle of oil than just the
zinc.