Fish-Hawk.Net

OK, Mr. J is asking some great questions about motor sizing for his rig to be. The advice, which I whole heartedly agree with is, as much as you can afford.

But, let me ask the question. Actually it is kind of 2 questions.
Here is my scenario (btw, I am just window shopping for now), my boat is rated for 130hp.

1) What are the repercussions of putting more horsepower on the back than the boat is rated for (i.e. in my case, putting on say 135 or 150).

2) I have actually seen some 130hp motors, but most appear to be the saltwater series and are 25" shafts (extra long). I only require a 20" (long) shaft. How would the longer shaft affect my set up/ handling.

thanks gang.

M.T. Livewell

Not an expert but my guess is the longer shaft would give you a better hole shot and less top end then the same HP with a shorter shaft. I wouldn't worry about going to a 135, there is not much difference in the weight or power so I don't think it would affect the performance and handling. Could be an insurance issue though if you go over the max. rated HP???

Does the weight of the motor start to play a role too... a bigger motor will be heavier and perhaps risk causing damage to the transom.. then you're in for some fun repairs

I'd question insurance too... i'm sure they'd make that a loophole to get out of paying you should something happen.

Here's the kicker (pun intended) let's say your boat is rated for 90 HP and you had a 90HP motor on it.. technically i wonder if a 10hp kicker would be allowed even though both would never be used together

My advice MT.. stay within the limit or buy a new boat.

It's not John. You're boat is rated for 90hp, then thats it. Putting a 10hp kicker would put you over your maximum allowed HP. The coast guard looks for this as well.

I didn't think so

You also hear of people getting a 115HP and putting 90HP decals on so they can run a faster motor on lakes which don't allow higher power motors.

For one thing you couldn't get insurance if it's over rated. Also not too many places will put motor on a boat that's over rated. MT how old is your 135? Because if it's an older style motor some of these newer motors are lighter and you might go faster with a new one. My brother in-law had a older 80hp on his aluminum fisher and bought a new 75 put on and gained over 5 mph.

Standard tournament angler procedure.

MT how old is your 135?

My motor is a 2000 johnson 2 stroke. But it is only a 90hp. And it is VERY difficult to find 130hp motors.
If I plan to upgrade, I usually see a)115s, b)some 125 mercs, c) some 130 yammy and other brands in 130 with XL shaft, and d) 135 of various flavors.
a) I don't see upgrading to a 115 being worth the added cost for what 25 horses would get me.
b) a 125 merc would not get me much more than a 115 johnson. Plus the cost to change out the controls and prop would lessen the value proposition even more.
c) again, different brands of motors, hence controls and props and/or XL shaft problem
d) I am passed the hp limit on my boat.

Standard tournament angler procedure.

Cute Markus, I know you're just kidding. But don't think I haven't considered putting some stickers on a 135 to bring it down a notch.

M.T. Livewell

If you overpower your boat you might not be able to fish some tournaments, some really check that!

BEN

Standard tournament angler procedure.

No Mark I beg to differ. I fish many tournaments and I never hide my 150 HP

Markus wrote:It's not John. You're boat is rated for 90hp, then thats it. Putting a 10hp kicker would put you over your maximum allowed HP. The coast guard looks for this as well.

Are you referring to the coast guard at the time of a boating accident as then there could or would likely be an issue(especially with an insurance company) if you are running over the recommend hp? If no accident has occurred, it is my understanding that the coast guard has no control over the horsepower on your boat as it is a recommended horsepower only; at least that is what I was told.

In the event of an accident, I don't think they would be too concerned with the hp of a kicker putting the hp over the recommended limit but I could be wrong in that thinking. In that case, however, the majority of all boats with electric trolling motors would also be over the legal limit especially bass boats that most of the time are maxed out and I'm sure a majority of people running transom mounted kicker motors as well.

Spinner is right about the Coast guard and insurance . As for putting a long shaft on your boat it can be done but you would have to put a jackplate or some outboard manufactors offer kits .
The Hound

My boat has a "maximum HP rating". It's not a recomended one - it's the maximum. I've been told that surpassing this maximum creates a safety issue for you and the surrounding boaters and that coast guards do look for it.

Unfortunately, I know my local coast guards better then I should. I'll ask one of them and see what they say.

MT - if you are planning to change your shaft length you might wish to ask Mrs MT's opinion on that. Especially seeing how it may affect your setup and handling.

Mick

Something else to consider.

Four Stroke engines can be a lot heavier than their two stroke counterparts. My four stroke 15 hp weighs 135 pounds. It's two stroke sidekick weighs 77 pounds.

I wonder if vertical weight is more of an issue than thrust or torque on the transom?

Legend