Hi Clint, Its not really a formula for kicker size but more a formula to know what your boat hull speed is. All boats when travelling at displacement (not on plane) have a maximum hull speed. Hull speed is the square root of the boat's length at water line. So if you have a 17 or 18 foot boat, your LWL (Length along water line) is likely 16 feet and your hull speed is 4 knots (or 4.60 mph as knots are = 1.15078 mph). If you have a 26 or 27 foot boat, you probably have a LWL of 25 feet and your hull speed is 5 knots (5.75 mph). You can push your boat faster, but in order to do so you either need to push a bigger bow wave or actually get up on plane. The hull speed is a good indication of how big a kicker you might need. I have an 8 h.p. Honda 4s highthrust, which does a fine job pushing it at up to hull speed which is fine for trolling. I sure as hell would not want to rely on it to get me out of a stormy sea. For those situations, more h.p. is better so a 9.9 or even 15 would be a much better choice.When I was looking at a small motor for my 17'er, someone on the forum offered up a formula to figure kicker size for whatever length of boat. Finaddict I think. I searched for the thread but couldn't find it. Maybe he could post it again. If he reads this. Please.
YES, YES, YES, YES, YES, YES, For something as small as a 14 I can see a 2.5. I was thinking more along the lines of a 16 to 19, FT.NO, NO, NO, NO, NO, NO!!!
I was using a 2.5 on my 14', as a kicker, plenty of power; but those 1 cylinder engines are awful in terms of vibration.
NO, NO, NO, NO, NO, NO!!!
I was using a 2.5 on my 14', as a kicker, plenty of power; but those 1 cylinder engines are awful in terms of vibration.