Choosing a Bow-Mounted Trolling Motor System: Part I

Trolling Motors for Skiffs

Electric trolling motors have come a long way in recent years. The options are more complicated than ever. So how do you begin to choose what motor and components make the most sense?

While trolling motors may seem counter-cultural in the world of poling skiffs, they’ve certainly changed the world of small-boat fishing.  There’s no doubt that advances in technology have made them more compelling  as alternative sources of power.

I’m still a hard-core poler and plan to remain so until my shoulders give out (and perhaps a bit beyond).  There are just too many advantages to poling, like the ability to react instantaneously and instinctively to what a fish is doing, and to be as quiet as you want to while doing it.


An angler’s eye view of the deployed bow-mount motor.

But last year I became curious about what a trolling motor could do.  I’d heard many stories of guides being able to hang in the current in spots where it was too deep to stake out, and using trolling motors to enter or exit flats where they didn’t want to run in water that was shallow enough that a combustion engine could damage the bottom.   But I’m also a person who prefers extreme simplicity when it comes to skiff rigging.  I tend to remove anything unnecessary from my boats.   So I wanted to discover whether the disadvantages of having the excess weight and complexity–not to mention the maintenance headaches–of a trolling motor system were worth the potential added performance.  In order to get the answers here I went right to the source, speaking at length with Joe Brown, head of marketing for Minn Kota, one of the top manufacturers of trolling motors and components.  Joe’s not just a guy who sells motors–he’s also got deep knowledge of how trolling motors work, and he maintains a surprising level of objectivity about his and other company’s products.

I had many questions for Brown.  Starting from scratch, I wanted an explanation of the differences between 12-, 24- and 36-volt systems, as well as what each offered in terms of performance vs. price and weight.    My second concern–which became larger as I found out what the new motors and associated technology could do–was how I should configure my system.  In the end, I chose a 24-volt saltwater system with built-in GPS and remote controller.  I also decided to go with a bow mount.

Minn Kota Contour Offset

Electric trolling motors have come a very long way in just the past 7 years, thanks mostly to the addition of map- and GPS-based functions.  Illustration courtesy of Minn Kota


Why a bow-mounted trolling motor?  One of the key advantages of fishing with a trolling motor is being able to fish solo.  Skiff fishing is traditionally a two-man sport.  But there are times and places where one simply wants to head out alone, and there are numerous answers to the “What do I do with my pole and my rod?” question, but none of them is perfect.   There are also some disadvantages to stern-mounted systems: namely steering becomes more of an issue because of windage on the bow and because of motor location and steering.   And bow-mounted systems are more suited to use of a new feature in GPS-based trolling motors–the ability of the motor to hold the boat in position.  This is because when the boat is being held from the bow, the boat aligns bow-first into the wind and remains quieter.  Stern-mounted systems work very well in a power-assist role for a poler, though, and in the role of replacing the outboard in entering and leaving flats do just fine.

Bow-mounted motors, on the other hand, tend to get in the way of the angler, being yet one more potential catch-point for fly lines and becoming minor obstacle when fighting fish near the boat.   They also typically extend beyond the side of the boat by at least a few inches when fully retracted and locked into their horizontal position on the deck.  (This is something to think about if you keep your boat in the water and tied off to anything other than a floating dock.)

Today’s trolling motors are much more sophisticated and durable than the motors of even 10 years ago.  GPS-signal receivers are standard in high-end models, and saltwater motor components are either completely sealed or corrosion resistant.  The technology is also changing rapidly into what is becoming a simple network linking components of trolling motors with other systems on the boat.  Right now, for example, you can link motor operation to GPS mapping on a separate unit.  It’s only a matter of time, in my opinion, before trolling motor control and even battery charging are linked to networked devices like phones and can be managed from outside the skiff.  But that’s getting ahead of the game.  I wanted my first installation to be as simple as possible, and to use only fully tested components.  So that’s what I focused on in my journey.

Brown’s answers to most of my questions are included in the interview below.   In Part II we talk about what system I chose, what the installed system looks like on my skiff, a 2013 Maverick HPX-V II, and how I decided on individual components.  Then I comment on my experiences with fishing with the trolling motor intensively for over a month.

But first, my interview with Joe Brown.

Joe Brown of Minn Kota

Joe Brown, marketing director of Minn Kota & Cannon

Advice from an Expert

Marshall Cutchin:  Thanks for taking the time to talk with us about trolling motors, Joe.  For flats fishing and near-shore applications, what role do you think trolling motors have?

Joe Brown:  Well, would I think I could go chase bonefish around with a trolling motor and catch them? Absolutely not. Bonefish don’t work that way. I might use it to get me to the place where I can start fishing for them, though.

In most other fishing applications, the key to not spooking fish is just not changing the trolling motor speed a lot.  I’ve actually driven right over snook, and they don’t even move.  And you’re a poler, so you understand: when both of your hands are on a push pole, you’re not casting.  Trolling motors free up your hands.  Plus we have quick-release brackets for our motors, so it’s much easier now than it used to be to get a trolling motor out of the way when you want to. It’s as easy as pulling a tie bar and unplugging the motor.

MC:  The choices in trolling motors and systems are pretty overwhelming these days.  Most of my questions come back to this: How does the typical boat owner decide on what trolling motor to buy?

JB:  Well that is the struggle. Quite honestly a lot of it is tribal knowledge. So if you were living in Key West right now, you’d probably ask your buddies. That means companies like Minn Kota can’t always get in front of the buyer with application-specific information. And quite honestly it has gotten a lot more complicated, in a good way, for the consumer.

So if you went to look for a trolling motor back in 1997, you would probably looked at rigidly fixed transom mounts so that you could motor along standing on a poling platform. Or you would have had a hand-controlled bow-mount motor.  Now, with electric-steer motors, you have a motor with a DC motor built into the bracket around the shaft in the motor housing, and you basically send an electronic or wireless signal to the motor, and it tells it what to do.

MC: Let’s talk about the things someone might consider when considering what trolling motor to buy. The most obvious question is probably How long can I use a trolling motor each day? I know that’s dependent not only on the motor size, but on the boat size and conditions, and whether I buy a 24-volt system or a 12-volt system, right?

JB: What you just asked is one of the most difficult questions to answer. First of all, the decision about what motor and system to buy really depends on your tolerance for weight in the boat. Some people just say “I’m going to take the trade-off of the 12-volt motor because I have to minimize the weight on the boat because of the water I’m fishing.” I’m a proponent of the highest-thrust motor that you have the tolerance for in terms of weight and dollars, because you’ll be running the motor at lower speeds to achieve the same results. You’ll also have better boat control because you’ll have more thrust to move the boat quickly when you need to if you need to turn it against the current or wind. This is an oversimplification, but you can say a 24-volt system vs. a 12-volt system will double the run time, and a 36-volt system would increase that by another third.

If you go out and turn your motor on at a 100%, it may last two or three hours. Unless it is a super-skinny boat, there are very few times when I would want to put a 12-volt system on a boat.

I’ll give you another example: I have a square-backed canoe that I have a 12-volt 55-pound-thrust motor on. 12-volt motors go from 30 pounds of thrust to 55 pounds of thrust. On a 24-volt system we go up to 70-80 pounds. And on the 36-volt system we go up to 101 pounds. So there are limitations within that when you look at the trade-offs in the motor size and the voltage, but generally speaking we look at pounds of thrust and relate it back to the voltage.

In my canoe, if I am going to go out in a big, windy lake, I have a small AGM battery and a lead-acid battery. So what I will do is bring both batteries some days and connect them in parallel so that I basically create a big 12-volt battery. That will basically double my run time. I make the trade-off with that of taking up room in my boat because I don’t want to get stuck on the other side of the lake because I’m loaded down with two kids in the canoe and am going at 100% most of the day and I don’t want to run out of juice.

Most of the time for flats boats, 24-volt, 80-pound systems are perfect. You get into the bay boats, that’s where the 36-volt system begins to make more sense.

MC: Is there any reason why I would choose a 70-pound thrust motor over an 80? Would it be cheaper and weigh less?

JB: Yes, it would. In any DC motor—like a drill or trolling motor—bigger equals more power and enable the motor to run cooler at the same power level. Going from a 70-pound to an 80-pound might make a difference of $200. But with the 80, you’re going to run at a lower power setting to get the same speed and get longer run times. And the weight difference is probably less than 5 pounds. So it goes back to that inherent trade-off: the more thrust you have, the less power you need to achieve the same speed.

Unless you are wanting to go from point A to point B quick, you’re probably going to stay at a constant speed, like when you are fishing. So if you are running at 3 miles an hour rather than 6 miles an hour, you’re using less thrust and less power, and the bigger motor will use less power to achieve either speed, and therefore have more run time. It’ll also get you from point A to point B faster.

MC: And I’m sure the weight and displacement of the hull and even the hull shape will have an impact on motor efficiency. If you have a super-narrow skiff, you could get away with a smaller system.

JB: Absolutely. And how much draft you are targeting, how much of a keel there is or flat-bottomed the skiff is… there are just a million variables.

MC: Speaking of draft, how much water do you have to have—or how far in the water does the motor have to be—to actually operate efficiently?

Trolling motor shaft length guide

Minn Kota’s guide to shaft length is helpful, but remember that you will probably be adjusting motor height depending on conditions and water depth. For example, when fishing in deep swells for tarpon, you’ll probably want the motor fully extended. A 54″ shaft offers the most flexibility on a skiff.   Illustration courtesy of Minn Kota

JB: Basically, to avoid cavitation, whatever the diameter of the prop is, you need at least the full diameter of the prop. You can cheat if you are in flat calm water. But if you are in rough water, you might add 5” to the depth to prevent cavitation.

MC: What about shaft length?

JB: The longer shaft gives you more flexibility in rougher water. But the trade-off is that you are going to have more sticking up on the front of the boat.

MC: And a longer shaft to deal with when the motor is up and locked down on the deck.

JB:  But six inches isn’t really that much of a difference in terms of whether it is going to get in the way, even if you talking about fly lines. It’s probably more important on a hand-controlled motor, where how tall you are and how high the motor is mounted above the waterline make the difference. Most 80-pound-thrust motors are mounted with 52” shafts and most 101-pound motors are 62”, and that goes back to the flats boat vs. bay boat scenario.

MC: How long would it take someone who is fairly proficient with wiring and tools to install a trolling motor system on a skiff?

JB: If you have wiring already run to the front of your boat, if you’ve never done it but were super-diligent—measuring three times and cutting once as far as drilling holes and stuff goes—I would say less than two hours.

MC: But you have to have that big stiff drink before you take the drill and start boring through the deck, though, right?

JB: Yeah, that’s where you measure it three times then have your buddy measure it four times. If you don’t have wiring already run to the front of the boat, that’s a whole different can of worms because it depends on how hard it is to fish the wire through and secure it.

MC: And of course there is the battery install time. Which depends again on space and positioning considerations in whatever skiff you are working with.  Are there any features of trolling motors that you think are key for buyers to look at when they are considering which motor and system to buy?

Minn Kota trolling motor corrosion protection

Minn Kota’s anti-corrosion coating represents the state of the art in saltwater component protection.  Illustration courtesy of Minn Kota

JB: The first thing I would say is, buy a saltwater motor. That’s really dumbing it down, but you’d be surprised how often that mistake is made. Some buyers might look at the difference in price and say “Well, I’ll just wash it off and I’m good.” At Minn Kota, for example, the reality is that the difference between the saltwater and freshwater motor is pretty big. The coating process on the metal, for example, under the powder coat are very different. Saltwater motors come with an anode that helps if there is any galvanic corrosion potential. And all the hardware is stainless steel, so it won’t corrode.

Since the 1980s at Minn Kota, all of our electronics have been urethane-encapsulated, so basically you could take our trolling motor, put it in the bottom of a swimming pool and hook it up to power and it will work. Beyond being sure that the boat wiring is of the correct gauge and that it is all fitted and secured correctly, the integrity of the motor electronics is the most important thing.

MC: Are there “saltwater motors” being made that don’t have all these features? How can someone know that they are getting a reliable trolling motor for saltwater?

JB: I would say this: You get what you pay for. There are a number of Chinese motors on the market, and I am comfortable saying that if there is a price difference, there’s generally a reason. And in service support as well.

MC: What about buying a used motor? Does that make any sense?

JB: Well I’m an EBay guy, so I’m not opposed to buying stuff in that way. But I personally would have a difficult time buying a trolling motor that way. You don’t know what’s going on internally with that motor or how it has been used. Even shipping a trolling motor is tricky. If they get dropped you can crack magnets and the chips can get into the armature, or there can be water in the lower unit if someone got fishing line around the prop and it ate into the seal. My advice is, with electronics and water, control your own destiny.

MC: Any other advice you would give to someone considering buying a trolling motor for their skiff?

JB: There’s so much new technology in trolling motor systems these days. I would just say Do your homework. You start with basically two options–hand-controlled or electric-steered motors—and it goes from there.  At Minn Kota, all of our motor testing requirement for a “good,” “better,” or “best” motor are the same. So for example our life-testing requirements are the same for a $99 motor as for a $2000 motor. So it’s not the kind of thing where you have to think about spending $1500 again next year or the year after. But once you put any motor on your boat, it’s not really easy to change your mind. So again, do your homework.

Another thing to consider is that you are probably going to have a fair amount of money invested in batteries with any system you choose. There’s probably a bigger difference in battery chargers than there is in the motors themselves. Be sure you charge those batteries right. There is a very big difference in battery chargers, and most batteries fail from poor charging vs. poor maintenance.

MC: What makes a bad charger? When it charges too fast or too hot or…?

Minn Kota 3-Bank Precision Charger

I chose the Minn Kota 3-Bank Precision Charger (MK-345-PC) to handle my three-battery system.  Minn Kota’s technology adjusts the charging “profile” to the ambient temperature, protecting batteries while allowing optimal charge speed.  Photo courtesy of Minn Kota

JB: Well, all of the above. Another example would be if a battery charger uses the same profile for a lead-acid and an AGM battery. The battery manufacturer has probably spec’ed different charge curves for those two batteries. It may not be hugely different, but it is different.

In the past three years we’ve come out with two new complete lines of chargers. We have this thing called automatic temperature compensation. At the end of every output lead, we have a thermistor—which is basically a thermometer—and it senses the ambient temperature where that battery is. By bank it adjusts the charging profile to not over- or under-charge the battery. At different temperatures, batteries have different voltage requirements for charging. Higher temperatures require lower voltages, and lower temperatures require higher voltages. Applying the wrong voltage at the wrong temperature is not a good thing. You’re either over- or under-charging, reducing the life of the battery and the capacity of the battery. Minn Kota Precision Digital chargers also allow you to independently set banks to charge by battery type, either AGM or lead acid, or gel.

MC: What about on-board DC alternator chargers that charge batteries while the engine is running? Do they make it possible to avoid charging altogether?

Minn Kota MK-2-DC alternator charger

Minn Kota MK-2-DC alternator charger.  Photo courtesy of Minn Kota

JB: Here’s what I would say as a generic statement: If you think you can run 15 minutes out to a spot and it’s going to charge your battery, it’s not going to work that way. You have to have pretty decent outboard motor on time for it to make a dent in a deep-cycle trolling motor battery. It’s a huge advantage, but it won’t replace a standard charger. It will mean that you don’t have to charge as often, and it might make it possible that you don’t have to charge every day.

MC: Let’s finish up by getting back to motor technology in 2013. What we have now are GPS-based systems that enable the motor to receive and communicate location data?

JB: Yes. Every electric-steer motor from Minn Kota comes standard with a key fob control and an optional foot pedal control. That technology came out in around 2003. And it allowed someone to stand on the platform and pole and not get in the way of the angler on the bow when he was steering the motor.

So fast-forward to 2009, when Minn Kota launched the i-PILOT, which is where we have GPS navigation built into the trolling motor. You can even buy that accessory now and install it into one of our older motors.  What i-PILOT does is give you the ability to have an “electronic anchor.” So let’s say you’re fishing a point or a channel and you want to stay in a spot but not have to put out an anchor and deal with pulling or releasing the anchor when you want to change position. The Spot Lock feature will hold you in a 5-foot diameter location, assuming you have a strong-enough GPS signal.  You can save those locations, and you can even record tracks. A perfect example is dock fishing at night. Let’s say you are zig-zigging in and out and around those docks. You can record a track up to two miles. You can come back to that track any time you want to and fish it from start-to-end or end-to-start.

We also built in cruise-control, so that the motor will adjust for waves, wind and current and keep you at a constant speed. Lastly we built in Auto Pilot, which allows you to point the motor on a certain bearing and the system will keep you on that bearing regardless of changes in wind or current. That feature used to use only a magnetic compass, but the latest system uses GPS-based tracking.  We also have i-PILOT Link, which connects Hummingbird fishfinders and navigation systems to the GPS system in the trolling motor.

MC: I can easily envision a time when the devices all have their own IP addresses on a wireless network and communication can happen from shore or a device anywhere else, for that matter.

JB: I don’t have all the specifics on that, but I wouldn’t be at all surprised if that was part of the future.


Continue: Choosing a Bow-Mounted Trolling Motor System: Part II (including installation photos, a list of all parts and a summary of our fishing test)