outboard horsepower and trolling speed

[newbytoboats]

a couple of years ago I bought a 14 ft gregor tinny with a six hp 4 stroke mercury. it's my first boat and motor so I've never known anything else. it trolls nice and slow like it should. but it takes forever to get from one place to another. i'd like more speed but have been told that if I go to a 9.9 or a 15 that I won't be able to go as slow when trolling. i need you old salts to tell me about the correlation between horsepower and trolling speed. i need advice as to whether to go for more hp, or leave well enough alone and be a turtle. it takes me 45 minutes to get to one of my favorite spots. that's a long time. but i don't want to lose my slow trolling speed. please advise.

 

[JimS123]

Re: outboard horsepower and trolling speed

I use a sonar unit equipped with a digital paddle wheel speed sensor. I troll in a current, and vary between up and downstream, so a GPS is worthless. With that as a caveat, my trolling speed with respect to the water is set at either 1.0 mph or 1.9 depending on the species I troll for or the direction of travel.

A 9.9 2-stroke on my 14' tinny works perfect at those speeds. It runs smooth and steady and i can run several hours without fouling the plugs.

 

[crabby captain john]

Re: outboard horsepower and trolling speed

I use a sonar unit equipped with a digital paddle wheel speed sensor. I troll in a current, and vary between up and downstream, so a GPS is worthless. With that as a caveat, my trolling speed with respect to the water is set at either 1.0 mph or 1.9 depending on the species I troll for or the direction of travel.

A 9.9 2-stroke on my 14' tinny works perfect at those speeds. It runs smooth and steady and i can run several hours without fouling the plugs.

Funny, my "paddle wheel" was showing 7MPH today while actual speed over ground was 3.1. You can troll with even a 15 if your boat is rated for it,, a $20 drift sock will regulate your speed.

 

[metriccrescentwrench]

Re: outboard horsepower and trolling speed

IMO you'd get a lot more enjoyment out of the boat if you can get from spot to spot faster. 6 HP seems pretty small for a boat that size as well. Also, have you considered adding a transom mounted electric trolling motor?

 

[roscoe]

Re: outboard horsepower and trolling speed

Or get a 15, and keep the 6 for trolling and emergency backup

 

[Georgesalmon]

Re: outboard horsepower and trolling speed

Your question was about HP vs trolling speed. So this is how I think. Just for illustration lets say you 6hp idles at 650 rpm with a 10" pitch prop. And lets imagine there is no slip. For every revolution on the prop you will go 10" forward. Now, get a 15hp that has a 13" pitch and also idles at 650rpm. Then for every revolution you'll go 13" forward. Just making up numbers here but you get the idea? I go with the drift sock or a couple of 5 gal pails with holes drilled in the bottom dragging from the forward cleats. Works great for me

 

[AChotrod]

Re: outboard horsepower and trolling speed

Depends what you are trolling for and where?
I think a 15hp would work if your trolling for pike/skis but may be a bit fast for bass, walleye, perch, crappie and such.

Get a 100 dollar 36lb trolling motor and a 15hp o/b and youll be set.

 

[newbytoboats]

Re: outboard horsepower and trolling speed

I have the trolling motor. But by 10 o'clock or so the wind makes it rough enough that I can't hold a line with the trolling motor. So it is of limited use on the lake I fish on.

 

[Home Cookin']

Re: outboard horsepower and trolling speed

Or get a 15, and keep the 6 for trolling and emergency backup

I don't think I'd put a 6 and a 15 on a 14' tinnie at the same time, if that's what you meant.

 

[izoomie]

Re: outboard horsepower and trolling speed

The new 4 strokes can troll all day and are super quiet. Get the maximum HP your boat will accept if you want speed. My 90 purrs like a kitten all day long. if you get a 10 or a 15 you'll be good.

If you want accurate speed indication you need a hand held gps or a fish finder / gps combo.

 

[JimS123]

Re: outboard horsepower and trolling speed

If you want accurate speed indication you need a hand held gps or a fish finder / gps combo.

Yeah, if you boat in a calm lake with no wind....LOL.

Where I troll the river current is about 1.5 mph. If I set the engine to do exactly 1.5 across the water and then turn with the current the GPS reads 3.0 If I do a 180, the GPS reads zero!

For trolling you need to know how fast the lure is traveling thru the water. A GPS won't tell you that unless the water isn't moving too.