For years I’ve been a proponent of Four Stroke vs. Two Stroke outboards. The arguments were several, though in truth mainly environmental. Four strokes are cleaner and quieter being the two main issues that tipped the scales.
I’ve had several 4 stroke engines over the years and they’re not bad. However we’ve had one problem as the children have gotten larger and I have failed to get any smaller, which is that the 9.8 Tohatsu we have just doesn’t have what it takes to get out of the hole and plane with all of us on board. We bought this engine when we moved from a roll up inflatable to a RIB, figuring the extra weight needed more push and this hull should be able to plane.
Sure, with just me and one of the children it flies – I’ve clocked 16+ knots by myself in it. But unfortunately if you add another 125-150 lbs or so past my body weight it’s all over for planing, and you now have a 4.5 knot wallow. While this is perfectly fine inside someplace like Block Island’s new harbor where the speed limit is 5 mph. But when you are trying out outrace a thunderstorm across a mile of open water it really is…inadequate. And wet.
The other difficulty we had was with my wife starting the engine. For some reason she just struggled with getting enough spin with the pull cord to get it to start reliably. What this equated too was a lack of confidence in taking the dink by herself – with is totally unacceptable in a cruising situation. We thought about a 4 stroke with an electric starter, or other options – and at that point it also seemed if we were to replace the engine why not get more HP so we can get it faster too.
So I did my usual thing and researched it to death. In taking the Outboard Engine Maintenance and Repair courses at New England Tech last fall I learned a lot more about the differences between a Two Stroke and a Four Stroke. A lot fewer parts on the two stroke, and the compression ratio is usually lower. Hmm…should pull more easily. I also posed the question to my friends over at Sailing Anarchy and got lots of good information there too.
I didn’t love the electric starter option for several reasons. It adds more complexity and weight to the engine – there is more to go wrong. You also have to deal with wires and a battery permanently installed and all that headache. It seems if there is a pull start solution that would work better there is no reason to add a more complex and expensive option.
So this past weekend I pulled the trigger and purchased a brand new 15 HP two stroke Yamaha. Why the two stroke? The newer ones are much cleaner than the older models, it is lighter, has higher low end torque (read: gets my tubby butt up on a plane more easily), should pull-start more easily, and have parts available for it anywhere. Also the weight to power ratio is better, this engine is lighter than a comparable 4-stroke, so I can hoof it up and carry it more readily.
But the small two stroke outboard is going the way of the Dodo in North America. Popular opinion has swayed against them, California emissions standards have taken their toll so this year will be the last year this engine – or any other small two-stroke – will be sold in the U.S. They will be around forever outside the U.S. but the major manufacturers have shut out the market here.