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Old 06 March 2010, 01:35   #1
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Twin small outboards on inflatable

Has anybody had any experience with small twin outboards on inflatable?
I have 8'8'' inflatable with Honda BF2 2HP outboard. It's not fast. I can barely make about 5 knots with just myself. But I love my outboard. I have an idea of twin mount. It's definitely going to add a redundancy. I'm having quite long trips along the shore from time to time. Rowing 5-10 miles will not be an option. Do you think twin 2HP is going to be twice faster? Is it going to be any faster/slower compared to 4HP outboard?
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Old 06 March 2010, 02:09   #2
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Originally Posted by ifeoktistov View Post
Has anybody had any experience with small twin outboards on inflatable?
I have 8'8'' inflatable with Honda BF2 2HP outboard. It's not fast. I can barely make about 5 knots with just myself. But I love my outboard. I have an idea of twin mount. It's definitely going to add a redundancy. I'm having quite long trips along the shore from time to time. Rowing 5-10 miles will not be an option. Do you think twin 2HP is going to be twice faster? Is it going to be any faster/slower compared to 4HP outboard?
Seems a small craft to be having twin engines,8'8,with two don t know what the weight would be ?,but if combined to the recommended weight for the transom,well,someone with more experience on here will be able to help you im sure,Happy sibbing
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Old 06 March 2010, 03:25   #3
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Originally Posted by ifeoktistov View Post
Do you think twin 2HP is going to be twice faster? Is it going to be any faster/slower compared to 4HP outboard?
You will probably go slower

Get a lightweight 5 horse perhaps?
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Old 06 March 2010, 11:31   #4
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Seems a small craft to be having twin engines,8'8,with two don t know what the weight would be ?,but if combined to the recommended weight for the transom,well,someone with more experience on here will be able to help you im sure,Happy sibbing
The inflatable is rated for up to 5HP, 55lb (25kg). Honda BF2 is 27lb, so it's 54lb total.
Should be OK for transom. I'm just not sure about performance.
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Old 06 March 2010, 12:34   #5
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It's definitely going to add a redundancy.
So will a set of oars.
I looked into putting twin 25's on my SIB and its not worth the hassle.
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Old 06 March 2010, 12:41   #6
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So will a set of oars.
I looked into putting twin 25's on ym SIB and its not worth the hassle.


I used to be a huge fan of twin engines, but various threads over the years on here have opened my eyes.

If neither performance nor initial cost are an issue then yeah - great. Otherwise not so much.
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Old 06 March 2010, 12:51   #7
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A 10hp 2 stroke should make it shift.
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Old 06 March 2010, 19:41   #8
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Ignoring the hassle of two throttles, you could probably steer using one engine. However, you won't get twice the speed from two engines. Also, if your single engine reaches maximum revs, as it should, then with a second one you will need to change the props for ones of greater pitch, you may find they aren't available. The wee Honda engines are noisy, I'm not sure I'd want to sit beside two of them at full chat. I used to run two 30hp on a five metre sib, it was a good arrangement.
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Old 07 March 2010, 16:38   #9
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You will probably go slower

Get a lightweight 5 horse perhaps?
I'll second that. Two engines for day-to-day boating is trouble. You have the combined steering and throttle to contend with. Get yourself a light-weight 2-stroke or 4-stroke.
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Old 08 March 2010, 03:24   #10
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Engines

If that Honda BF2 engine weighs 27lb you could get a Mercury/Mariner 6hp and that weighs 26lb.
I know you said you wanted to keep your existing engine, but you could use it as a spare....the Mercury 6hp on my 2.8m SIB will achieve 14.5mph and that's with two of us on board.
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