# Smallest planing dingy/motor



## asdf38 (Jul 7, 2010)

I have contradictory goals for a tender

1) Suitable for towing and/or storing from/in my 26'
2) Capable of being carried/wheeled ~750' by myself
3) Suitable for an ~8 mile passage (from my house to my boat).

So basically, like I said, I want the absolute smallest boat/motor combination capable of planing (with one person). 

So I wanted to know people's experiences with small motors and small boats with decent planing performance.


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## hpeer (May 14, 2005)

> PERFORMANCE&#8230;.This is where Porta-Bote really excels over ordinary rigid craft and inflatables. Imagine being able to get up on a "plane" using a tiny 2.5hp outboard. You can when one person is in the boat and at the helm. Porta-Bote takes a standard "short shaft" engine. Do you know what kind of power it takes to get an equivalent sized aluminum or fiberglass boat up on a plane? You would have to invest in a high priced, exceedingly heavy engine that weighs as much as the hull!! And remember, you have to lift this cast iron monster over the transom to get it installed.


Porta Bote | Porta Bote | Hi Performance

They sell a wheel kit to roll it.


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## jeffzee (May 30, 2007)

i have a walker bay 270 air floor with a 6hp suzuki, great combo. the walker bay is only 55lbs! it being light was the reason i purchased it as i wanted something i could tow behind my san juan 7.7 without being slowed down. It planes well with the 6, an 8 would be even better!


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## Ilenart (Jul 23, 2007)

I have a Aquapro SLR710 inflatable dinghy which has an Alum hull. The dinghy is 7 ft 10" / 2.4m long weighs 26kg / 57lbs and I have a Mercury 3.3HP outboard. With just me in the boat and so long as I sit in the middle seat the dinghy planes, probably 10-12 knots, though I have never measured it. I weigh around 70kg / 150 lbs and even one of my kids onboard is enough to stop the dinghy planning. Note that the 3.3HP has a pretty small integrated tank. For a 8mile trip you probably want a separate fuel tank, which you can place forward to help balance the dinghy.

I think the reason this dinghy planes so well is due to the aluminium hull.

Ilenart


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## lancelot9898 (Dec 30, 2008)

Not too long ago I sold my 25 year old Archilles inflatable and motor. The dinghy weighed in at around 100 lbs and had a hardwood floor and I think it was 9 feet long. The Nissan 5hp 2 cycle would plane with myself at 200lbs and wife at 120lbs. With that hardwood floor it was difficult to assemble on deck and I now need something smaller. With a smaller and lighter dinghy I could probably get by with a smaller outboard and still plane. I did experiment around with different props, but can't remember what pitch I ended up with.


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## ReefMagnet (May 8, 2008)

Planing depends on the load and length of the dinghy. The shorter the dinghy, the harder it is to get up on the plane. My 9 ft fibreglass hull rib will plane with just my 100 kg weight and a 3.3 hp outboard (I have to sit in the middle as well). With the wife onboard as well (weight unknown  ) and her luggage the same dinghy won't plane with our 9.8 hp o/b. We once had a 12 ft inflatable dinghy with an 8 hp o/b and it would - just - get on the plane with the same load.


Sent from my GT-P1000 using Tapatalk 2


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## Multihullgirl (Dec 2, 2010)

TAKACAT Lite T300L with 8hp engine, although if you want to keep it really light, the 2hp will push the dink just fine, but it won't plane


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## MikeGuyver (Dec 13, 2008)

West Marine AL290 (9'10") w/ older 8 hp Honda. I weigh in at a semi-chubby 220. On a plane the Garmin said 21kts. With wifey aboard it has trouble climbing the bow wave, but will plane at 15kts.


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## asdf38 (Jul 7, 2010)

Thanks for the posts.



Ilenart said:


> I have a Aquapro SLR710 inflatable dinghy which has an Alum hull. The dinghy is 7 ft 10" / 2.4m long weighs 26kg / 57lbs and I have a Mercury 3.3HP outboard. With just me in the boat and so long as I sit in the middle seat the dinghy planes, probably 10-12 knots, though I have never measured it. I weigh around 70kg / 150 lbs and even one of my kids onboard is enough to stop the dinghy planning. Note that the 3.3HP has a pretty small integrated tank. For a 8mile trip you probably want a separate fuel tank, which you can place forward to help balance the dinghy.
> 
> I think the reason this dinghy planes so well is due to the aluminium hull.
> 
> Ilenart


This is a good datapoint. I currently have a merc 3.3hp and I really don't want to go larger. At ~28lbs it's quite a jump to any larger (or newer) motors.

But it sounds like I have at least some hope with smallish inflatable, although a rigid floor adds cost.

Porta-bote:
I'm well aware of porta bote and I find it pretty intriguing. However I havn't answered to my satisfaction whether the 8' will plane well with the 3.3hp. I'm actually staring at an 8' for sale right now in the neighboring town, and that fact is partly what drove to start this thread - I wanted to see what other possibilities are out there.

While I like the porta-bote it certainly has pros and cons. My biggest concern is that it's a bit less suited for towing. An inflatable is more forgiving in that it can flip, bounce off the mothership etc without any real consequences. And while the porta bote could be stowed on my 26, the seats and transom apparently take up quite a bit of space, on top of the windage the hull would add if tied to my lifelines.

It's all a lot of compromises.

If any one else has any more testimonials for boat/motor combinations that would be great.


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## jimgo (Sep 12, 2011)

Why not strap the poratbote down flat, rather than against the lifelines? Strap it to the transom, or next to the mast. Also, why not ask the owner if you can take it for a ride with your engine (or his/her's, if they have one)? That will give you a sense for how it performs. If you take the boat out with your engine, offer to leave a security deposit.


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## asdf38 (Jul 7, 2010)

Well, continuing my quest I picked up an 8'6" air floor off ebay (Mercury, 2011, $300). It's a good boat and a decent craigslist pickup.

As an aside my 6'8" turns out to have a leak and my 3.3hp didn't pump water properly and had a stuck carb (both craigslist). Over the last 2 weeks I completely took apart the 3.3 to fix both things.

Anyway, the datapoint I wanted to share is that I can't quite plane the 8'6" air floor with the 3.3hp. I thought my odds were 60% but it doesn't quite work. It's still a nice boat/motor pair however.


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## northoceanbeach (Mar 23, 2008)

I've recently bought a nine foot rib with a six horse four stroke. I'm hoping it will plane just me and up to fifty pounds of gear. I weigh 160.


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## eherlihy (Jan 2, 2007)

I have a West Marine SB275 and a Mercury 3.3 two-stroke. This setup can get my 190lb butt on a plane after ~45 sec. at WOT.


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## MikeOReilly (Apr 12, 2010)

asdf38 said:


> Porta-bote:
> I'm well aware of porta bote and I find it pretty intriguing. However I havn't answered to my satisfaction whether the 8' will plane well with the 3.3hp. I'm actually staring at an 8' for sale right now in the neighboring town, and that fact is partly what drove to start this thread - I wanted to see what other possibilities are out there.
> 
> While I like the porta-bote it certainly has pros and cons. My biggest concern is that it's a bit less suited for towing. An inflatable is more forgiving in that it can flip, bounce off the mothership etc without any real consequences. And while the porta bote could be stowed on my 26, the seats and transom apparently take up quite a bit of space, on top of the windage the hull would add if tied to my lifelines.


A bit late to the conversation here, but my 10' portobote planes with ease using our our 3.5 hp engine.

Storage of the seats might be an issue on a 26' boat. On our 37-footer they store easily on deck in from the cabin. The bote sits on the side deck against the cabin.

I only tow our bote for short hops with benign weather forecasts. It tows very easily, but could flip in a big wind, and then would be serious drogue. You'd have to cut it loose. Luckily it's pretty easy to disassemble, so we're rarely tempted to tow. If you were planning to tow I would bring it right up to the stern, and lift the bow out of the water. That way you could secure it laterally against being blown over. We can't do this b/c of our transom-hung rudder and windvane.


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## hopcar (Jul 6, 2013)

Smallest and lightest boat that will plane with one person?
Got to be a 6 ft. Fliptail. They can also be made in 7 foot or 9 foot.
Fliptail planes


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## asdf38 (Jul 7, 2010)

hopcar said:


> Smallest and lightest boat that will plane with one person?
> Got to be a 6 ft. Fliptail. They can also be made in 7 foot or 9 foot.
> Fliptail planes


Well that's the winner so far.



eherlihy said:


> I have a West Marine SB275 and a Mercury 3.3 two-stroke. This setup can get my 190lb butt on a plane after ~45 sec. at WOT.


Hmm that's a good data point. That's just a bit bigger than mine and the wooden floor is probably an advantage over my low pressure air floor (3.6psi floor, 6psi keel). But that's the same engine I have.

One problem is that I can't get the engine to full RPM's because the boat speed is too low, peaking at 5.4 knots. The engine peaks at about 2/3 throttle and doesn't speed up (actually slows down a bit) beyond that. Presumably because of all the drag on the prop (Right?)

I'll check my prop and if I currently have a 7" pitch I'll order a 6" and give it a try. I'm guessing it still won't be enough, but for $15 it's worth a try.

Porta-bote:

One general problem I have towing is that my transom hung rudder prevents me from pulling a dingy up on the stern. This makes the porta-bote slightly less attractive because it's harder for me to tow and prevent it flipping.

EDIT: Also I contacted porta-bote and in regards to their 8' they said "2.5hp might do it and 4hp will definitely get you up on a plane."

The owner selling his 8' porta-bote on craigslist says he does get on plane alone, with a merc 3.3 2-stroke.


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## hopcar (Jul 6, 2013)

"The engine peaks at about 2/3 throttle and doesn't speed up (actually slows down a bit) beyond that."

I had an engine that did exactly that. It turned out to be a partial blockage in the fuel system. It would run normal up to about 3/4 throttle but push it past that and the engine would actually lose power. 

What was happening was that beyond 3/4 throttle the engine wouldn't get any more fuel but the carb was still opening, this let in more air and caused the engine to run too lean.


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## eherlihy (Jan 2, 2007)

asdf38 said:


> One problem is that I can't get the engine to full RPM's because the boat speed is too low, peaking at 5.4 knots. The engine peaks at about 2/3 throttle and doesn't speed up (actually slows down a bit) beyond that. Presumably because of all the drag on the prop (Right?)
> 
> I'll check my prop and if I currently have a 7" pitch I'll order a 6" and give it a try. I'm guessing it still won't be enough, but for $15 it's worth a try.


Other possible issues:

fuel/air mixture too rich
too much oil in fuel/oil mix 
old gas
when is the last time that you changed the lower unit oil?

PortaBote's are great but they are FUGLY!uke


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## asdf38 (Jul 7, 2010)

hopcar said:


> "The engine peaks at about 2/3 throttle and doesn't speed up (actually slows down a bit) beyond that."
> 
> I had an engine that did exactly that. It turned out to be a partial blockage in the fuel system. It would run normal up to about 3/4 throttle but push it past that and the engine would actually lose power.
> 
> What was happening was that beyond 3/4 throttle the engine wouldn't get any more fuel but the carb was still opening, this let in more air and caused the engine to run too lean.


Hmm well this strikes a cord because I already dealt with the carb being stuck (open at the time) once.

So alright I'll take it apart again, it's not that hard. And since the first time I've found the service manual online and bought some carb cleaner. So I can do a better job this time.

If I can get an extra 1/3 throttle that would make a big difference.

Though come to think of it, I can test this in a bucket to see if it has a similar problem there too.

eherlihy:
Gas is new, oil mixture should be ok and lower unit was last year according to paperwork I got with the engine. Although maybe I'll change it anyway, because why not.


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## ehmanta (Sep 12, 2006)

Porta-Boats are a great concept, but I personally can't get over how ugly they are! Maybe if they weren't so floppy looking. 

A possible solution is to build one yourself with ultra light weight materials. Chesapeake Lite Craft is one source for plans/kits. 

I built a Dudley Dix design (Dixi 8)with 1/4" ply and beefed up the transom. I can almost plane with a two HP by myself, probably would with that 3.3hp.


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## hopcar (Jul 6, 2013)

"So alright I'll take it apart again, it's not that hard. And since the first time I've found the service manual online and bought some carb cleaner. So I can do a better job this time."

If you've already cleaned the carb, you might want to check the rest of the fuel supply system before you go back into the carb.


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## asdf38 (Jul 7, 2010)

Well it turns out I can get the engine to 100% by fiddling with the choke (I have a separate thread dedicated to this problem).

But after doing that I got my 8'6" air floor on plane, barely, by running wide open and lying in the front on flat water in a local lake. "On plane" was 7.8 knots.


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## Classic30 (Aug 29, 2007)

asdf38 said:


> Well it turns out I can get the engine to 100% by fiddling with the choke (I have a separate thread dedicated to this problem).
> 
> But after doing that I got my 8'6" air floor on plane, barely, by running wide open and lying in the front on flat water in a local lake. "On plane" was 7.8 knots.


Sounds like you might need a bigger outboard..


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