Dink OB - Long Shaft vs Short Shaft

[boatpoker]

I had a 9'2" Aquapro dinghy ... aluminum hull, If I remember correctly it weighed 89lbs. It had an 8hp Suzuki on it and it would do 24mph (GPS).

A buddy of mine was North American 3-point hydroplane champion in days of old and he told me he could get it to 30mph just be raising my short shaft so that the anti-cavitaion plate was 1" below the transom instead of the existing 3". As confirmed by GPS .... he was right.

[monte]

That's interesting. Our 3.1m dink is 50kg and 9.9 Johnson 36kg and flat chat is around 20kn

[44'cruisingcat]

Originally Posted by Terra Nova

Having owned several versions of the especially excellent 3.5hp Tohatsu/Nissan 2-stroke (without shift), when a pair of brand new 3.5 long shaft outboards became available, locally, a friend and I pounced on them. As you can no longer buy them in Ca. But it was just ridiculous on my 2.85 Avon roll-up. And so I passed it along to another friend. Presently have a near mint 3.5 Tohatsu short shaft (plus a Yamaha 3 and Johnson 15). The short shaft 3.5 will easily plane my dink, solo. But the long shaft would not.

One problem not yet mentioned is how a long shaft motor unmercifully twists the wooden transom on a non-rigid inflatable, due to the increased lever arm.

I guess you haven't even bothered to read the original post in this thread? It's a fibreglass RIB, not a wooden transom non rigid.

It's over - let it go.

[Terra Nova]

44--you, of all people, should never try to tell others what to do or say.

[44'cruisingcat]

Yep, can't refute the argument, attack the person. No surprises here.

[a64pilot]

Originally Posted by monte

That's interesting. Our 3.1m dink is 50kg and 9.9 Johnson 36kg and flat chat is around 20kn

20 Kts on 10 Hp means it's set up pretty good, I have about the same dink with twice the HP, but I am a fat guy.

[a64pilot]

We didn't have GPS back then , but I want to think we were running about 40 MPH on those 8' hydro's, but then again, I bet I was all of 50 lbs too. The boats were light, have no idea of the weight, but two kids could carry one easily.

[a64pilot]

Maybe this boat, but we ran tiller motors, no steering wheel
Build Your Own Boat: POPULAR MECHANICS, March 1965

[44'cruisingcat]

Originally Posted by boatpoker

I had a 9'2" Aquapro dinghy ... aluminum hull, If I remember correctly it weighed 89lbs. It had an 8hp Suzuki on it and it would do 24mph (GPS).

A buddy of mine was North American 3-point hydroplane champion in days of old and he told me he could get it to 30mph just be raising my short shaft so that the anti-cavitaion plate was 1" below the transom instead of the existing 3". As confirmed by GPS .... he was right.

That is interesting. Probably worth checking the cav plate height on any dinghy, whether it has the "right" shaft length or the "wrong" one, since even "right" can be wrong...

[txh2oskier]

Originally Posted by colemj

Sigh.

Dude, I have been SUPPORTING you this whole thread. It was two other posters who called you lazy and buying wrong stuff.

I have spent quite a few posts fighting that those statements FOR you.

Mark

Obviously I'm the one that needs to go back and re-read previous posts. I apologize for being snippy. Must have got up on the wrong side of the bed that day.

[valhalla360]

Long shaft is perfectly fine. If you race your dingy you may lose a slight edge but for normal use, you would be hard pressed to notice the difference.

The idea that you will die in a horrible accident is just a joke.

One positive side for a long shaft...the mother ship came with a spring loaded outboard bracket on one of the transoms. You can mount the dingy motor and it works as an emergency backup. A long shaft would be very useful if there is any wave action to help keep the prop in water.

[Ribbit]

Originally Posted by colemj

I get it now. You are only here to wind things up.

. . . . . .


Mark

Unfortunately the likes of Terra Nova usually run long lists of sock puppet accounts to further their aggravation. Forum Mods can usually get on top of this nuisance factor by blanket banning their IP's.

Still, this one is now on the ignore list (that makes two for this forum, I usually leave a forum permanently if it hits 15 rapidly - a number that shows the Mods aren't taking things seriously enough, to the usual destruction of the forum, which I don't hang around to see).

Funniest spin out I saw was in my 10ft grp dinghy. Mr 'not ever paying attention to anything, ever' Steve, who had borrowed it (he'd somehow managed to leave his attached to his mooring 40+ miles down the coast, but had somehow remembered to take the outboard off it), managed to get it to spin out with his 2.2hp Mercury (rebadged Tohatsu two stroke) short shaft, and he was lying in the dinghy bilge in zero seconds flat, with his legs in the air (all he was lacking was sails, and he could have got places).

If I'd only had a camera . . . . . .