LM18 performance

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ShaneM
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LM18 performance

Post by ShaneM »

New to the forum here. I’m considering a LM18 build in the next year or so. Could anyone give me specs in regards to how it drafts, handles, and planes with the tunnel in place? I’m considering a 40hp for it. I’m in coastal NC and have a lot of flats around here with generally <5 mile runs between the ramp and fishing location.

TomW1
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Re: LM18 performance

Post by TomW1 »

Hi Shane and welcome to the Forum. The LM18 would be a good flats boat for you off your flats out your way. To start your thinking you will need a jack plate to raise the motor up to take advantage of the tunnel. As far as the 40HP I don't know if you need it as this is such a light boat and a 40 weighs so much more than a 30HP, check into that. Especially since your runs are less than 5 miles. Most 40's weigh as much as 50's & 60's. A Yamaha 40 is over 240lbs while its 30 is 214.

There have been several LM's built and I am sure the guys will tell you there stories.

Good luck on your decision.

Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978

jonnymac
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Re: LM18 performance

Post by jonnymac »

Check this thread out as a starting place.

viewtopic.php?f=25&t=65173&hilit=lm18&s ... 13b7122102

jonnymac
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Re: LM18 performance

Post by jonnymac »

and this thread. viewtopic.php?f=2&t=62619&sid=da7435f90 ... fc9d0dba7d

this is probably one of the nicest ones on the site.

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cape man
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Re: LM18 performance

Post by cape man »

While this boat was designed wider than the FS18 in part to allow the tunnel option, no one on the forum has yet built one with it. You will lose some performance (speed and fuel efficiency) with any tunnel, but if you are only running 10 miles round trip so what.
I bought a finished hull that I haven't started on, so have read all the posted builds including the two referenced above. I'm leaning more towards the smaller tiller steer engine, maybe even the Yamaha 25, a hydraulic jack plate, and no tunnel. Should be able to run in 1' and idle or pole in much less.
I wouldn't worry too much about the weight difference between a 30 and a 40 hp Yamaha as it is just 36 lbs and you'll get 10 more hp. If you build the tunnel you'll want the extra hp.

Whatever you do, please post a build thread. Not only will you get tons of advice and help (most of it helpful and wanted :roll: ) but others can learn as you go.

I love the lines and program for this hull, and fishing the shallows in NC is the kind of place it will do great.

Welcome to the disease! However, please be aware that once infected there's no cure for Boat Building Virus.
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