outboard for achilles inflatable

[bobsadler]

have purchased a 9ft 6in achilles air-floor and am about to buy the outboard. have been thinking a 6hp was what i would get but wondered if a 4hp would be sufficient.

anyone with a similar achilles (or another similar air-floor) got any thoughts?

thanks

[SilentOption]

Beyond the obvious, what are you planning to use the boat for?

If all you plan to do is idle back and forth from your boat to the dinghy dock then hp is of little consequence.

If you want the boat to reach its safe and efficient top speed with the rated max load then you need to read the plate on the transom and see first what is suggested. If you have the LSI 290 they suggest 8 hp max. And 6hp as standard. I think 4 might be far too little when the boat has a load. When a soft floor inflatable bends as often happens when its near the max load and or the air pressure is low, it will take even more HP to push it along. Thats a considereation also.

I have a 9.9 on a 10 foot avon RHIB and the boat is just slightly underpowered with 4 adults. When its just me and some groceries its more power than I need. That boat is rated for 15hp so I am just about at half the recommended power.

When we had a catastrophic transmission meltdown on the ICW I put the RHIB along side and warped my 44 foot sailboat over 15 miles. This saved a huge tow bill and worked marvelously.

More HP that day would have helped somewhat but less would have certainly been a problem.

How will the motor be stored? If it has to go on and off the boat everytime you use consider the handling gear you will need. More HP equals more weight.
Will it spend most of its time hanging on the rail? Thats a consideration also. Will you have to beef up your rail to hold a larger outboard?

[bobsadler]

i think i'll go with the 6hp. i''m heading for the med so generally in marinas or fairly sheltered anchorages.

i've just got rid of a 10 1/2ft rib and 15hp yamaha. rail bracket was for the 15hp so no problems there.

the air-deck plus a 6hp mercury will weigh about 2/3 of the rib alone.

i plan on dismounting the davits as they make stern-to mooring difficult. i'll keep them safe until the boat is back in NZ

[Talbot]

The davits can be useful for stern to mooring. They mean that you can have a plank to the shore, and use the davits to keep the shore end high enough to stop the rats using it as a highway!

[Hud3]

I have that same dinghy, and use a 5 hp 2-stroke Tohatsu. It will plane with just me and groceries, etc. in it, but not with my wife and me. She doesn't like to go fast anyway, so that works fine for me.