Is 6hp outboard enough power?

[Kenatsea]

LOL!!!
This thread is quite funny. I started reading this because I am also trying to decide on a new motor for my new dink. I have a few small outboards currently, a 8 hp Yamaha 4 sk., a 6 hp Tahatso 4 sk., a 18 hp Nissan 2sk. (this one I baby cause it can't be replaced in the US). All of these are already committed to a different boat each. But I need one for the mothership dink in Mexico. I have been seriously thinking of a 9 hp 2 sk., as you can still pick them up in most of the world.
But what is so charming about this thread is that I too have motorcycles as a second passion and was not expecting to see them noted here. You folks rock!

Ken S/V Azul.

[OneBoatman]

In general, it's not usually good to put the largest motor a dinghy may be rated for as the go to for expecting to achieve plane. Most dinghies are not meant serve their captains on plane, instead meant to take you and your cargo to and from shore short distances. Same is true of many tenders and launches these boats have different purposes and different hull shapes than speedboats. RIBS that have more than just a rigid bottom which also have a rigid fiberglass transom or an integral welded Aluminum transom will nearly always handle motors up to their rated max better than a pure inflatable or the various hybrids with folding transoms. For those without an integral rigid transom going to the max shortens their service life, and they will come unglued much sooner than if used with lighter motors, and not driven on plane frequently which raises the stresses.

[j.g.evans]

I agree with the consensus the you are unlikely to plane with 2 people and 6 HP. My experience is if you are not planing then the ride can be quite wet. If you are not going to plane then why struggle with the weight of a 6 HP. Go for 2-3 HP.
What I used for many years is a 10' RIB with both a 15 HP to go distances and 2 HP to "commute" short distances in calm water. I could plane with 3 people.

[Peeew]

I think the best solution for you would depend on how you will use it. In my mind a 6 is good for short bits, ball to shore etc. Limited gear and people. I use a 9.9 Yamaha on a light, aluminum 9ft dinghy and it works for two well. Occasional use for more is ok but slow. Since I tend to do some longer runs on the dinghy to spearfish, explore creeks etc I wouldn’t be happy with any less power.

[steffan]

Originally Posted by Mirage35

FWIW

I had a 6 hp Tohatsu on our ultralite 8 foot RIB. It would plane with just me (150 lb soaking wet) on board, but that's it.

Exactly my experience with the same conditions and outboard!

[jimellifritt]

Originally Posted by osprey877

I have just bought a new 9' RIB. It is fairly light at 80 lbs and is rated for 10hp.
I would like to power it with a new 4 stroke 6 hp outboard (2 stroke is not available in US/Canada) as this is relatively lightweight to hang off my pushpit and for my wife and I to manhandle. It is also the largest outboard that has a an integral gas tank. I want to avoid the hassle of filling and storing a separate tank, the minimum size of which seems to be about 5 gallons. I currently have an integral tank 2.5hp and fill it from a couple of 1 gallon jerry cans that fit in my vented cockpit storage bin. I am hoping to keep using the same system.
My question is whether or not a 6hp outboard is powerful enough to get the RIB onto a plane at WOT when carrying the 300 odd lbs that constitute my wife and I. The dealer says yes, but I'm hoping someone with actual experience can chime in. Most people seem to use a 9.9, but all seem to agree that is way more powerful than necessary if there's only 2 in the boat, and the 9.9 is considerably heavier than the 6. Will the 6 work, or do I need to bite the bullet and get an 8 or 9.9?l Thanks

I have a 6hp Nissan on a 10ft AB with aluminum floor. I can get on plane with just me, but not with 2 people. The tank is in the bow locker.

[wolfring]

I have owned a 10' dinghy with a 6 HP outboard for many years. It only planed with one person. And it was "squirrly" as another member said. Even with only two it did not plane.
While I liked the weight I could deal with by myself, I often wished I had bought 8HP.


Wolfring

[W5PAD]

I have a 9.5' RIB with a 6 hp 4 stroke outboard. I've had this set up for ~15 years and have cross the Pacific with it. It works fine except with more than one person it will not plane. And with one person, it just barely gets on plane. Thus, I mostly go slow and enjoy the scenery.

[Seaward22]

Originally Posted by osprey877

I have just bought a new 9' RIB. It is fairly light at 80 lbs and is rated for 10hp.
I would like to power it with a new 4 stroke 6 hp outboard (2 stroke is not available in US/Canada) as this is relatively lightweight to hang off my pushpit and for my wife and I to manhandle. It is also the largest outboard that has a an integral gas tank. I want to avoid the hassle of filling and storing a separate tank, the minimum size of which seems to be about 5 gallons. I currently have an integral tank 2.5hp and fill it from a couple of 1 gallon jerry cans that fit in my vented cockpit storage bin. I am hoping to keep using the same system.
My question is whether or not a 6hp outboard is powerful enough to get the RIB onto a plane at WOT when carrying the 300 odd lbs that constitute my wife and I. The dealer says yes, but I'm hoping someone with actual experience can chime in. Most people seem to use a 9.9, but all seem to agree that is way more powerful than necessary if there's only 2 in the boat, and the 9.9 is considerably heavier than the 6. Will the 6 work, or do I need to bite the bullet and get an 8 or 9.9?l Thanks

I have a 20’7” LWL, 2200# displacement . I run a 6hp , long shaft, 4 stroke Nissan. Only challenge I ever had was going against the tide at the Bascule bridge next to Ocean City,MD inlet where the rip rap was going by painfully slow. Can’t imagine you would have any issues with a 4, 5, or 6 hp if it’s set up correctly.

[Icarus]

Not enough... You need a 10hp...

[Jackdaw]

I have a 98lb 9.6' rib with 6hp 4-stroke Tohatsu, and it does not go on a plane with 220lb myself, even when I sit further from transom using a tiller extension. I am considering buying a 9.8hp instead, it's the lightest one in the 2-cyl 4 stroke range.

[Goodxcharly]

I use a 6hp Tohatsu on an Achilles Ls 77, 7’8”. Which it easily plains with 200#.
Tohatsu builds lighter outboards though just as reliable as the name brands, Honda etc.

[svmatilda]

My experience is that you will more than likely will be disapointed with this setup.
We had a 6hp suzuki (big disapointment) and I could only get our tender up on the plane with just me in it, and that was it. This outboard was a high performance 4 - 6hp and as such brought along its own unreliability problems.

If I put in some resupply items the 6hp would not push us up on the plane. We were glad to sell it off and put on a 9.9hp 2 stroke, for almost the same weight as the 6hp 4 stroke, a game changer and made our shore trips much more enjoyable. We would often have the two of us and a months supplies in the tender and up on the plane going back to the boat.

[Boatguy30]

Almost definitely not. There is rooming the market for a more powerful 8hp/ 65-70lb 4 stroke. The original honda Classic 8 was super chunky looking and not much heavier.

6 hp will plane one person, very unlikely 2 even if 300 pounds

[delucia]

My 6hp Marc gets my 9' rib on plane with me - 195lbs - but not much more. You could go more HP but that's also a lot more weight. I'm finding the 6 hp is about all I can lug on and off the mothership.