what size outboard

[rigpigpaul]

Hi all,
I have just bought a 2.5 metre inflatable dinghy. I would like to drive it up on to the plane with at least two people on board. What size outboard would I need and should it be two stroke or four? There are no davits on my boat but I intend to fit a lifting arm on the rail.
regards Paul

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[snowleopard]

5hp will just about make it. 8-10 will certainly do it but check the max size rating of the boat.

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[charles_reed]

I suspect

you'll exceed the rated outboard power if you use much above a 6hp motor.

Check the plate on the back - that tells you the maximum power for the annex.

Unless you have either a RIB or one with an inflatable keel planing it is going to be fairly challenging in any seas but a dead calm.

My last inflatable, with inflatable floor only, just got onto the plane with 3.5hp on a 2.1m annex, the same motor gets onto the plane, with 1 only on a 3.6m with inflatable keel. With neither could you plane with 2 up.

The rated power on the 2.1 annex was 1.6kW (about 2.5hp).

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[charles_reed]

I suspect

you'll exceed the rated outboard power if you use much above a 6hp motor.

Check the plate on the back - that tells you the maximum power for the annex.

Unless you have either a RIB or one with an inflatable keel planing it is going to be fairly challenging in any seas but a dead calm.

My last inflatable, with inflatable floor only, just got onto the plane with 3.5hp on a 2.1m annex, the same motor gets onto the plane, with 1 only on a 3.6m with inflatable keel. With neither could you plane with 2 up.

The rated power on the 2.1 annex was 1.6kW (about 2.5hp).

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[charles_reed]

I suspect

you'll exceed the rated outboard power if you use much above a 6hp motor.

Check the plate on the back - that tells you the maximum power for the annex.

Unless you have either a RIB or one with an inflatable keel planing it is going to be fairly challenging in any seas but a dead calm.

My last inflatable, with inflatable floor only, just got onto the plane with 3.5hp on a 2.1m annex, the same motor gets onto the plane, with 1 only on a 3.6m with inflatable keel. With neither could you plane with 2 up.

The rated power on the 2.1 annex was 1.6kW (about 2.5hp).

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[JerryHawkins]

We've got a 2.7m Quicksilver air deck and a Tohatsu 8hp. This gets on the plane very easily with 2 people and stores. In fact it will quite happily reach 16kts (according to hand held GPS) in flat conditions!

Cheers,

Jerry

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[pragmatist]

Coo ! Keep an eye out for you then shall we !

<hr width=100% size=1>a pragmatist is an optimist with a boat in the UK

 

[AIDY]

GOSH 16 Knots. Are they all Bow Lines ?

<hr width=100% size=1>/forums/images/icons/wink.gif <font color=blue> Regards Andy </font color=blue>

 

[JerryHawkins]

You needn't bother, you won't find me doing that speed through quiet anchorages or where a speed limit applies!

It is nice to have the extra power in reserve sometimes, e.g. we can outrun the wah from inconsiderate "stinkies" or local harbour tugs that kick up quite a wave even though they probably are sticking to the speed limit!

Cheers,

Jerry

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[jeanne]

Jerry, you are kidding yourself!

I have yet to see someone driving a Rib which can plane travelling in any other fashion. In the process you miss the chance of making new friends [ too fast to exchange any more than a meaningless wave], and quite often, you make enemies! At any rate you make wakes, and there is little to choose between a 2.5 M Ribs wake at close range and an inconsiderate harbour tug.

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[Moose]

Re: Jerry, you are kidding yourself!

"2.5 M Ribs wake at close range and an inconsiderate harbour tug"

You must be joking!! A small RIB going fast makes absolutely no wash at all.

<hr width=100% size=1><A target="_blank" HREF=http://www.phantom37.co.uk>http://www.phantom37.co.uk</A>
Moose

 

[jeanne]

Re: Jerry, you are kidding yourself!

They will still be trying to plane when overloaded, and then the wake is serious. And a harbour tug doesn't pass a few feet away when you are going for a dip.
How many 'quiet' anchorages are quiet any more?
And what is the hurry? the one thing that a cruising yacht has got is time.

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[scarlett]

Not true!

Getting onto the plane ---- coming off the plane --------and turning ALL cause a wash and big enough to fill another inflatable poodling along. I have had mine filled by the wash.

Even though you may see no one on a boat they may be below trying to prepare food, as I was when some inconsiderate 'jolly boat' came into port from a 'superyacht'.

Why is that someone in a rib needs to enter a 'quiet' anchorage, do a semicircle through the boats and then go off to the next one. Are you looking for your friends? How about trying to radio them to find out where they are? Have you thought that they are maybe hiding from you.

When I am the dictator 2 hp will be the maximum for any tender or rib or PWC! And 2 knots the maximum speed for any boat in any anchorage with another boat already there.

Sorry but you have shot your bolt. In your foot.



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[Anonymous]

Re: Not true!

>>When I am the dictator 2 hp will be the maximum for any tender or rib or PWC!<<

That seems rather unreasonable to me. We are planning to get a planing RIB as a tender for use in the Med while we are at anchor. We envisage wanting to use the tender to travel several miles along the coast and planing is the only sensible way to do that. A decent seaworthy tender is also required when the sea gets a bit choppier - you don't want to get stranded ashore when the wind picks up.

>>And 2 knots the maximum speed for any boat in any anchorage with another boat already there.<<

What do you mean by "2 knots"? Through the water or over the ground? I've often moored where significant streams flow and a 2 knot limitation would be absurd. The essence of the matter is 'reasonable and considerate behaviour' but of course there is no way to measure that or 'convict' someone of contravening the code.

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[scarlett]

Re: Not true!

When I am dictator I have no plans to be reasonable. But I promise there will be a few changes around here.

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