Automobile engines require four strokes to complete a cycle and are much heavier because they require extra systems and components, which make them cleaner and more efficient. Description from washingtonpost.com. I searched for this on bing.com/images
Wish i'd of kept it! ...how many of you think that when it comes to thinking about your old sports moped? The Honda SS50 was powered by a 50cc four stroke engine mated with a four speed gearbox (later models had the luxury of having 5 gears!). Build quality was as you would expect from a Honda - the usual thick coats of paint and chrome we're standard on the SS50 and it really showed against it's competitors.