On Tue, 21 Nov 2006 13:13:14 -0800, ajw wrote:

I am a member of a Scuba diving club and we are investigating replacing
our outboard engines.

We currently have two Zodiac 5m inflatable boats (not RIBs) with 40HP 2
stroke Mariner outboards. These are reaching the end of their lives and
we are looking at replacing them.

With the new legislation coming in we are looking at 2 stroke vs 4
stroke. I am aware that few people use 4 strokes on inflatables and
fewer would manhandle them down beaches removing and replacing them
daily as we do.

4 strokes are more efficient, reliable, quieter, and cleaner than 2
strokes, but they are heavier. However, a newer 4 stroke may be lighter
than an older 2 stroke. So look at specs when you shop.

I believe there are newer 2 strokes that meet environmental
regs -- I don't know about in your size/power range though.

Comparing specs is one thing, but consider what's available to you
locally, parts and service wise. Everything's a compromise.

Does anyone have any experience of using 4 strokes on inflatable boats
in this way? Are there any implcations to the angle you can carry/store
them?

The small Hondas I've used can be laid on their side indefinitely. I
don't know about larger ones.

Matt O.