Outboard Smack-Down: Two-stroke vs. Four

Both two-stroke and four-stroke outboard engines have, as a rule, come a darn long way in the past decade or so. We used to have to deal with smelly, noisy, unreliable engines that took the pleasure right out of running your boat. But today’s outboards, be they new-tech two-strokes or modern four-strokes, are a whole different ballgame. In fact, they’re clean, quiet, and highly reliable. So, how are you supposed to know which is the best one to choose? Here are a few key factors to keep in mind when comparing the two types:

* When it comes to efficiency, direct-injected two-strokes and today’s four-strokes are actually extremely competitive. In fact, most of the time they burn within 10-percent or so of each other, and between the different makes, models, and sizes, you can’t accurately state that one’s more efficient than the other.

* If low noise and vibration levels are an important factor to you, then a four-stroke is the way to go. Yes, today’s two-strokes are far better than those of yester-year. But as a general rule of thumb they still aren’t as quiet and smooth as four-strokes. As the size of the motor shrinks, however, this difference becomes less and less obvious.

* Those who don’t like the smell of oil will want to go for a four-stroke. But these will be really picky boaters – today’s two-strokes put out a tiny fraction of the fumes that older motors emit.

* Those who want the best HP-to-weight ratio will want a two-stroke, in most but not all cases. There are some modern four-stroke powerplants available that can match two-strokes in this regard, but only in a limited power range (as in, 150-hp and up).

* When acceleration is important, it’s hard to beat a two-stroke. But again, a few limited models of four-strokes can now match a two-stroke’s acceleration.

* Maintenance is, IMHO, a wash. Yes, many modern two-strokes can go longer and farther between regular maintenance, and no, there’s no four-stroke oil to change. But that really isn’t a huge deal for anyone with an iota of hands-on initiative and most of today’s four-strokes, again IMHO, have a slight edge for reliability, which saves on your down-time in the long run. Note: I recognize that some people will disagree with me on this; it’s just my personal experience, and you may have found otherwise.

Truth be told, considering how much better today’s outboards are than they were just a few years ago, you’re unlikely to be disappointed no matter what you buy. So, which is it going to be, a two-stroke or a four? Let the smack-down continue…

Today’s outboard engines have come a long, long way.