Choosing The Right Size Trolling Motor For Your Boat

Ways to choose the right size of trolling motor for my boat.

​​For fishing enthusiasts, it doesn't matter if fishing for pleasure or even for the competition is classified as a sport or not. For them, it’s a game...a game recognized as a game of stealth.  If you are one of them, for sure, you appreciate what a boon trolling motors are to you and to the rest of the fishing brotherhood. You don’t only have total control of your technique always; trolling motors also allow you to move easily and stealthily from one spot to the other and catch more fish in the process.


(​Watch this helpful video if you don't feel like reading the rest).


​What Is A Trolling Motor?

A trolling motor is an independent or self-contained motor attached to either the stern or bow of an angler’s boat that has an electric motor, controls, and propellers. Although. A gasoline-powered motor used in fishing which is not the boat’s principal source of propulsion could also be called a trolling motor. This trolling motor is usually elevated from the water to lessen the drag when the vessel’s main engine is running.

Two kinds Of Trolling Motor

Transom Mounted Trolling Motor

A trolling motor used for game fishing is mostly a secondary source of power or propulsion and is usually anchored on the transom close to or beside the main outboard motor or on a bracket specifically built for it. A transom mounted trolling motor is adaptable to any kind or style of craft but works better for smaller boats as well as canoes and dinghies. 

Bow Mounted Trolling Motor

​A trolling motor is also used as backup power for maneuvering the boat with precision to allow the angler to cast his rod to the spot where the fish is. Trolling motors intended for this purpose are usually anchored in the bow of the boat.


To install a bow mounted trolling motor there must be enough space in front and a plate or mounting bracket to attach the housing. For this trolling motor to work, a flat bottom boat for fishing is required.

The advantage of a bow-mounted trolling motor is that it provides greater maneuverability and excellent control to allow the angler to fish more efficiently and easily. The increased maneuverability is because a bow-mounted trolling motor pulls the boat through the water as compared to a transom motor that pushes the vessel. If you have a big boat like a 14-foot or even bigger that has space for a bow mounted motor, this is exactly what you need.

Two kinds Of Bow-Mounted Trolling Motors

Once you have made a decision to buy a bow-mounted, the next thing to consider is whether you will get a hand operated or foot operated bow-mounted trolling motor. Both, had its advantages and disadvantages Choosing one that gives you the most comfortable use should be enough criteria. 

​Hand Operated

​Advantages:

● Free your hands for other tasks
● Not difficult to control
● Can be positioned anywhere in the boat

​Disadvantages:

● The pedal is an added clutter on deck
● There are more parts that could malfunction or break
● Some models are said to have a slower response time
● Hand control

​Foot Operated

​Advantages:

​● Clutter-free deck
● Response is real-time

Disadvantages:

● The hand needs to be always on the rod
● Mounted only from the bow

What Is Thrust, And Why Is It Important?

Trolling motors use battery power to move a boat. The amount of strength or power required to propel a boat through the water is known as “pounds of thrust”. This power rating is a universal rating to all kinds of motors and is probably one of the most critical features to consider in the selection of the right size of motor to match your boat. If there is no sufficient power behind you, it will be almost impossible to work your boat through high waves, wind and weedy conditions. 

There are a lot of factors to consider in making a decision on the required power for the boat to attain optimum performance. These factors include the weight and length of your craft, whether you fish alone or with the company, whether you carry a lot of gear or whether you fish in unfavorable conditions such as rough waters and high winds.

To give you an idea as to the minimum amount of pounds of thrusts applicable to boats according to boat length, take a look at this thrust chart:  

Minimum Thrust Required

​Boat Length in Feet

​Pounds of Thrust Required

​12

​30

​13

​30

​14

​32

​15

​36

​16

​40

​17

​50

​18

​55

​19

​65

​20

​74

​21

​74

​22

​101

This chart is based on “normal fishing condition". If you fish under other conditions or with another person or persons, or you carry a lot of heavy gear, your best option is to consider a motor with higher thrust level than what is recommended in the chart.  

Some experts believe that buying the biggest motor is the best option but within reason of course. You would not want a large, powerful motor to dwarf your boat. On the other hand, a trolling motor that is underrated for your boat could cause you a lot of headache and anguish once you are out in the water. 

Remember though, a higher pound of thrust will not necessarily make your boat move faster. A 30-pound thrust motor will move your boat at the same pace as a 55-pound thrust motor. The maximum speed of a trolling motor is 5 mph whatever its pound thrust.

Voltage And Batteries Of Trolling Motors

Trolling motors are available in 3 power systems, 12, 24, or 36 volts. A 12-volt trolling motor is operated by the 12-volt deep cycle marine battery, a 24-volt motor by 2 12-volt batteries and a 36-volt motor by 3.  

The easiest and cheapest to work with is a 12-volt trolling motor. However, it somehow lacks the thrust and staying power of the other two. A 24-volt or 36-volt trolling motor can give an angler a longer time to stay in the water to fish since they provide more power and thrust while drawing lower amps.  

If you own 16-foot craft or smaller, a 12-volt high-thrust model will be a satisfactory choice. However, if you have a bigger, longer boat, you need to go to a 24-volt or 36-volt system so that you can go fishing hassle-free. 

It is not advisable to economize on the batteries. A high-quality deep cycle marine battery which is specifically designed for electric motors is your assurance of longevity and maximum power. Providing one for your trolling motor will give you peace of mind when you are out on the lake fishing.

Other Features To consider When Buying A trolling Motor

Shaft

Shaft length is critical for the maximum control of a boat. If you choose a shaft that is too short, the propeller may not be adequately submerged in the water during rough weather or other unfavorable conditions. On the other hand, if it’s too long, you might have a problem operating in shallow waters. The shaft length most appropriate for the size of your boat will guarantee safety. 

The shaft length depends on the height of the stern or bow. For deep V boats, a longer shaft is required. On the other hand, a shorter shaft is appropriate for canoes.

Propeller

The design and style of the propeller are quite typical whatever the model of trolling motor you choose.  The makers of this motor do not really offer options for prop design. And motor buyers too are not very particular on the design and style of props of a trolling motor, as long as it moves the boat.

With regards to blades, the options are either a 2-blade or a 3-blade. There are a number of differences between a 2-blade and a 3-blade propeller, but buyers don’t really get to choose when they buy the motor. Usually, a 2-blade prop comes with smaller trolling motors. A 2-blade prop has a more limited forward thrust but is also less wear on the motor giving it longer battery life. Larger trolling motors with a pound thrust of 80 lbs or above normally comes with 3-blade propellers. The additional blade is needed to move the bigger boat. Although it is more wearing to a battery, these larger trolling motors are normally operated on 36V to make up for it.  

Conclusion

​As to the question; what size of trolling motor do I need for my boat, I believe that has been answered earlier. It will depend on the size of your boat. If your boat is a small craft like a canoe, a 12-volt motor will be adequate, However, if your craft is a big one either a 24-volt or 36-volt trolling motor will be needed. 


But the criteria for the most appropriate trolling motor does not stop on the size. There are other things that you need to consider so that you have a hassle-free and enjoyable fishing expedition. … pound thrust; transom or bow, and if a bow - hand or foot control; length of the shaft and more.

Hi, I am Mark Neal From San Francisco in the United States. I’m the founder of BATTERY MAN GUIDE since last December in 2017. My team from Philippines  and i have been working very hard to write lot of articles about “product reviews” and “how to guide” on batteries we believe they will help for what you look for! You may sometimes find some incorrect grammars and less engagement dialogue but we will improve our contents continuously along the way. To be honest, we are still not well established battery website, but we are trying to become an authority in this industry in the future by providing valuable information for our readers. With that being said, thank you for visiting at BATTERY MAN GUIDE and we are looking forward to having a great relationship with you!