Author Topic: How much power for 18 foot standard  (Read 5109 times)

Offline Slappy84

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How much power for 18 foot standard
« on: June 10, 2016, 01:25:43 AM »
Planning on commencing my build of an 18 foot standard with cuddy and deck in a few short weeks. Is a 60hp 4 stroke enough power?
Will mostly run solo or with one passenger 90% of the time and doing 10 - 20 mile round trips with the occasional longer run offshore if conditions are right. Icebox and gear weight estimate 200 - 300 pounds. if I need more than 60hp will have to go 2 stroke as i haven't found any bigger 4 strokes under the 300 pound transom limit with the exception of Yamaha f70. Prefer 4 stroke as there are some lakes I might visit from time to time that have banned 2 strokes. Not interested in going too fast but would like to be able to travel at 22 - 26mph when solo without revving it's guts out and to be able to get up on the plane still with the occasional heavier load (2 or 3 passengers).

I understand there's no free lunch here. Any input on options would be most welcomed.

I have considered building a widebody and powering up a bit but a smaller standard skiff will fit most of my needs best and budget as well. If I went bigger the trailer and engine would probably cost me an extra 3 to 4 thousand dollars plus the extra cost in the hull which I can't really justify right now considering what most of my use will be.

Cheers,
Mike.

Offline Dave Wright

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Re: How much power for 18 foot standard
« Reply #1 on: June 10, 2016, 07:55:33 AM »
Planning on commencing my build of an 18 foot standard with cuddy and deck in a few short weeks. Is a 60hp 4 stroke enough power?
Will mostly run solo or with one passenger 90% of the time and doing 10 - 20 mile round trips with the occasional longer run offshore if conditions are right. Icebox and gear weight estimate 200 - 300 pounds. if I need more than 60hp will have to go 2 stroke as i haven't found any bigger 4 strokes under the 300 pound transom limit with the exception of Yamaha f70. Prefer 4 stroke as there are some lakes I might visit from time to time that have banned 2 strokes. Not interested in going too fast but would like to be able to travel at 22 - 26mph when solo without revving it's guts out and to be able to get up on the plane still with the occasional heavier load (2 or 3 passengers).

I understand there's no free lunch here. Any input on options would be most welcomed.

I have considered building a widebody and powering up a bit but a smaller standard skiff will fit most of my needs best and budget as well. If I went bigger the trailer and engine would probably cost me an extra 3 to 4 thousand dollars plus the extra cost in the hull which I can't really justify right now considering what most of my use will be.

Cheers,
Mike.


An 18 foot standard with, cuddy, deck and only a 200 pound load, and with solo operator would just meet your needs with a light 40 HP two stroke. It would not meet your needs with ANY additional weight whatsoever, you would be wide open and unable to achieve the speed you want. With three people aboard and load you would barely get on plane.

I only used the 40 hp so I can't definitively say how much power you might need. I would guess that only the lightweight 70 hp Yamaha 4 stroke might make you happy.

Offline Slappy84

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Re: How much power for 18 foot standard
« Reply #2 on: June 11, 2016, 04:35:57 AM »
Thanks Dave,
I've always admired the look of your set up. Whats your cruise speed and top end speed with the 40hp?

Offline Dave Wright

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Re: How much power for 18 foot standard
« Reply #3 on: June 11, 2016, 07:16:47 AM »
Thanks Dave,
I've always admired the look of your set up. Whats your cruise speed and top end speed with the 40hp?

Thanks, it was a nice little boat. I sold it 5 years ago. I posted a speed vs rpm chart on the old site. The boat would do 30 mph wide open, when new, one person, couple of six gallon tanks, anchor, a few tools, no load to speak of.  I don't know about "cruise" speed in little non commercial boats, I'm very, very happy with 10 to 15 mph.