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Choosing between a 15" or 20" transom

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I'm looking for a 1448 flat jon, and I'm wondering if there's an advantage to either transom height? I doubt I will use an outboard motor on it, and I would be buying a new trolling motor for it. 

 

I assume there would be less chance of water splashing in over the transom, but is there any other difference other than motor shaft length?

 

Thanks.

 

 

  • Super User

The higher transom would be used if you were going to put a jet outboard on the boat. 

  • Author

Thanks. That would be the only reason to get a 20" transom?

20" transom is the standard really, it allows for a wider selection of outboards, and it also sits the boat higher in the water increasing freeboard for running in rough water.

The boat would be easier to sell with a 20" transom as well down the road.

  • Author

How does the boat sit higher in the water? When I looked on the Lowe and Alumacraft websites, the side heights were the same for both the 15" and 20" transoms. 

  • Super User

I'm wondering that myself.  I guess that extra 5" had some type of magical flotation cell in it.

 

The only reason I would get a 15" transom if there was an option was if I already had a short motor to put on it.

Another thing to remember, if you plan to pick up a used motor, I think the smaller motors are more common in short shaft than in long shaft.  Once you get above 25hp, then that trend seems to reverse. 

For years you didn't have the option, it seems most boats 15' or shorter had 15" transoms and 16' and longer had 20" transom

  • Author

Thanks. That makes sense. 

  • Super User

A word of advice, unless you know you are going to be fishing an electric only lake, plan on getting you a 25hp motor.  25 is the size I would recommend on that size boat.  Much smaller on that size boat and you have one or two people and gear, it's not going to perform very well.  A 9.9 will push it, but you will be surprised how slow a 9.9 seems on a bigger lake.  You could just do like me, I have a 4hp, 9.9hp, and a 25hp I use un my 1436, depending on where I'm going to be fishing.  Once you start using the boat and enjoying it, you will most likely want to go to a gas motor also.  That opens up a whole new world on larger lakes.

With that in mind, do some research on Used 25's in your area and see what's mostly available, that might help you decide.  Now, if you feel you would bite the big one and buy a new motor "when" you do decide to add a gas motor, then it doesn't matter.

  • Super User

^^^^this^^^^

I will add outboard engine shaft lengths are designed to be used on the same transom  height; i.e., 15"  shaft OB is measure from the mtg clamp top surface to the cavitation plate to be compatible for 15" transom height. 20" std / long shaft is compatible for 20" transom. When you look for an OB engine check the shaft length to be compatible to your boat.

Tom

  • Author

Thanks all

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