Trolling Motor Selection Tips

Thrust, shaft length and features are just a few of the many things to think about when it comes time to pick the perfect trolling motor.

In this article, we'll discuss the key factors you need to understand to ensure you get the right motor for your boat.

Thrust

The issue of thrust is the biggest factor people struggle with when selecting a trolling motor, and itʼs an important issue to get correct.

Too little thrust and your boat wonʼt be able to move well in the water. Too much thrust and youʼre spending more than you need.

There are two metrics for determining the proper amount of thrust - boat weight and length.

Boat weight is by far the best determinant. If you know your boat weight, use this metric to determine thrust needed. However, itʼs often hard to determine boat weight and length is often used as a good proxy.

The charts below will give you a good idea of how much thrust youʼll need for your boat:

These are recommended minimums, so if you often fish in wind or strong currents, you may want to step up to the next level of recommend thrust.

Also, when considering boat weight, make sure to figure in the weight of boat passengers and equipment.

Transom vs. Bow Mount

Almost all trolling motors will mount either to the transom (rear) or to the bow (front) of the boat.

Transom mount motors are most commonly used with small to medium sized boats, are more affordable and are fairly straight forward.

Bow mount motors are usually used with medium to larger sized boats, cost significantly more and are usually compatible with a host of features such as foot pedal  control, wireless control, AutoPilot technology and others.

The type of mount you need will be dictated by your boat size and fishing style.

Small boats with open bows will almost always use a transom mount motor as bow mount motors require a flat platform on the bow for mounting.

Larger boats will often be compatible with both transom and bow mount motors, and the choice will come down to budget, boat size and fishing style.

If you want both hands free for fishing, youʼll want a bow mount foot pedal controlled motor.

If youʼre on a budget and donʼt mind steering the trolling motor by hand from the back, a transom mount motor would be a fine choice.

For more information on selecting the appropriate transom mount motor, please see our article on Transom Mount Motor Selection.

Shaft Length

Shaft length is another issue that causes confusion when selecting a trolling motor. A trolling motorʼs shaft is the straight rod that connects the head of the motor to the propeller, and is measured in inches. The process for determining the correct shaft length varies slightly based on whether you have a transom or bow mount motor.

Transom Mount Motors

Transom mount motors should have approximately 20” to 25” of the shaft underwater to ensure proper performance.

To determine the shaft length you need, measure the distance from the transom of the boat to the water line, and add the 20” to 25” submersion factor.

For example, if itʼs 20” from your transom to the waterline, youʼd want a shaft that was 40” to 45” long.

Bow Mount Motors

Because the bow of a boat often moves up and down more than the transom, the submersion factor for bow mount motors is a bit larger.

Bow mount trolling motors should have 25” to 30” of the shaft underwater to ensure proper performance.

To determine the shaft length you need, measure the distance from the bow of the boat to the water line, and add the 25” to 30” submersion factor.

For example, if itʼs 20” from your bow to the waterline, youʼd want a shaft that was 45” to 50” long.

If in doubt, always go with a longer shaft length than a shorter one. While you can always stow your motor or adjust the shaft length upward, itʼs impossible to compensate for a shaft that is too short.

Brand

While there are many electric trolling motor manufacturers, the two largest and most well known players are Minn Kota and MotorGuide.

Both are well respected and while Minn Kota is more popular, there are large regional pockets where the MotorGuide trolling motor is definitely king.

Both Minn Kota and MotorGuide make quality motors, and you should feel comfortable that youʼll receive a quality product no matter which one you decide on.

If you donʼt have a strong opinion either way, find the best trolling motor that fits your boat and budget needs regardless of brand name.

Additional Features to Consider:

Apart from the basics - thrust, mount, and shaft - there are a number of other features and options to consider.

While these arenʼt necessary for motor operation, they can serve to make your time on the water much easier and more convenient:

Quick Disconnect Plates - Disconnect plates, or trolling motor release mounts, are an optional accessory which allow you quickly remove your motor from the boat.

These are very convenient if you want to use a single motor with multiple boats, or if you park your boat in a public area and are worried about theft.

Built-In Transducer - Some models have a sonar transducer built-in to the bottom of the shaft for use with popular fish finders.

Having a transducer built-in reduces cord clutter and significantly reduces the risk of breaking a transducer attached manually to the bottom of the motor shaft.

AutoPilot - Some high end bow mount motors are compatible with AutoPilot, a feature that keeps your boat on a fixed heading automatically. This is very convenient for fishing shorelines, shelves or for maintaining a heading over open water.

Wireless Control - Some upper-end models feature wireless boat control, which lets you control your motor with a remote control from anywhere on the boat! Apart from being convenient, wireless remotes serve to reduce the clutter associated with traditional corded foot pedals.

Battery Gauge - Nothing is worse than unexpectedly running out of battery life when fishing which is why built-in battery life indicators are great. They let you know how much life remains so you can plan, and use your motor, accordingly.