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How To Measure Trolling Motor Shaft Length

How To Measure Trolling Motor Shaft Length. It is essential, for a number of different reasons, that you choose the appropriate shaft length for your trolling motor.

To begin, in order to get the most possible thrust, it is essential to keep the propeller submerged during the whole journey. Choosing the longest shaft available may seem to be a simple option; but, doing so puts your motor head and propeller in danger of coming into contact with rocks, weeds, logs, and other obstacles that may be present in the water.

The performance of the motor suffers as a direct consequence of the greater drag that is caused by having a longer shaft length. Cavitation bubbles may be avoided by ensuring that the shaft length is accurate.

These bubbles are loud and scare away fish. In the following, we will walk you through the suggested processes for selecting the appropriate shaft length for your requirements. Check out complete list of deep cycle marine battery.

How To Measure Trolling Motor Shaft Length
How To Measure Trolling Motor Shaft Length

What is trolling motor

An angler’s boat is outfitted with this self-contained device or trolling motor, which has an electric engine, propeller, and controls. The device is attached to the boat. It enables a boat to remain in one place even while battling against wind or tide and does so without the need to set a real anchor.

To explore regions that would normally be inaccessible due to shallow water, tilt the outboard engine up and out of the water and utilize the trolling motor instead.

Components of the Trolling Motor

  1. The electric circuit board that is responsible for controlling the activities of the motor may be found within the power head, which is located on top of the motor assembly.
  2. The power head and the propeller hub are both connected via the shaft. Because it is hollow, it may also function as a conduit for cable. It is possible for it to be constructed out of aluminum, chrome, stainless steel, or a graphite composite. Composite shafts are able to create steering torque in strong motors despite their small weight, stiffness, resistance to impact, and extraordinarily long lifespan.
  3. The propeller shaft and the electric motor are both contained inside the waterproof hub of the propeller.
  4. Two, three, or even four blades may be found on a propeller. Weedless props feature leading edges that have been carefully designed in order to prevent weeds and kelp from fouling them.

Comparison of gas and electric trolling motors

It’s a common misconception that the only kind of trolling motors available today are electric versions, but this couldn’t be farther from the truth. Gasoline motors are still commonly used in the trolling industry.

Trolling motors that are gas-powered

Gas trolling motors are miniature replicas of Evinrude’s 1909 invention, the outboard motor. Evinrude’s motors propelled boats propelled by propellers. In most cases, they are equipped with a four-stroke engine that delivers between 2 and 6 horsepower.

This makes them more powerful than electric trolling motors. As a consequence of this, they are also much quicker than electric trolling motors, with maximum speeds that are more than 4 to 5 knots.

Trolling motors that are electric

O. G. Schmidt of North Dakota is credited with the invention of the electric trolling motor in 1934. (who went on to found Minn Kota the same year). Electric motors have the potential to provide up to 120 lb thrust, which is about equivalent to 1.5 horsepower.

Because of this, they are noticeably less powerful than those fueled by gasoline, and as a result, their maximum speed seldom goes over two to three knots. You can also check out lithium marine battery.

Choose the appropriate trolling motor shaft length

One of the most important steps in selecting the ideal motor for your boat is figuring out the appropriate length of the shaft for the trolling motor. It will assist in ensuring that the shaft of the motors is long enough to keep the propeller submerged for a minimum of 12 “below the surface of the water given the circumstances of your particular fishing trip.

It is also important to ensure that the propeller does not emerge from the water when the boat is in motion (a.k.a.”cavitation”). On the other hand, although it is essential to have a shaft that is of an appropriate length, you don’t want it to be so long that it gets caught on the ground or that it is difficult to store.

Length of the Bow Mount Shaft

When it comes to bow mount motors, getting the right shaft length is even more important (as compared to transom mount). Bow-to-water distances have a greater propensity to differ from one boat to the next, and the bow tends to move about on the water a great deal more than the transom does.

As a result, it is essential to make certain that you choose the appropriate length for the shaft. The first step is to determine the distance between the horizontal mounting point on the bow and the waterline. Add 20 inches to this distance “to these standards of measurement.

In most cases, the length of the shaft should be either equal to or larger than the quantity in question, but it should never be shorter. The following are some potential additional aspects to take into account:

  • If you fish in difficult seas regularly, then add 5 to the total “to the lengths that are indicated down below. This will assist the propeller in remaining submerged despite the increased deck bob that occurs in seas that are rough or subject to wind.
  • If you are directing a hand-controlled engine while standing up, add 12 to the distance “according to the transom length recommendations shown below. By moving the motor tiller to a more elevated position, this will make steering the boat more simpler and more pleasant.

Measuring the shaft

When measuring the length of the shaft on a trolling motor, start at the bottom of the motor head and work your way up to the top of the motor compartment.

Transform mount motor

The first thing you need to do in order to determine the appropriate shaft length for your boat is to take a measurement of the distance from the mounting place on the transom all the way down to the waterline. The necessary shaft length may then be obtained by taking this measurement and adding 20 inches to it.

If you are on the fence between two sizes, it is best to choose the bigger of the two. It is not possible to lengthen a shorter shaft, however adjustments may be made to a larger shaft. If you find yourself in more challenging conditions on a regular basis, we recommend adding an extra 5 inches to the overall length of the shaft.

Trolling motors that are operated by hand or foot also exist

There are primarily three techniques to direct a trolling motor, which are as follows:

  • Tiller
  • Hand-held remote control
  • Foot pedal

Tillers are often the controller of choice for inexpensive trolling motors since they are by far the most user-friendly alternative and also come at the most affordable price. The disadvantage of selecting this alternative is that in order to direct the trolling motor, you will need to be positioned quite close to it (though you can improve matters a bit by using a tiller extension).

Trolling motors that are of a higher quality often come with a remote control that can be held in one’s hand and that digitally regulates the trolling motor in order to direct it. You are free to manage your trolling motor from any location on the boat as long as there is a clear line of sight between the remote control and the motor itself. This is one of the many advantages of having this setup.

Last but not least, some high-end trolling motors are equipped with a foot pedal that may be used instead of a remote control to operate the motor. The most significant benefit of selecting this alternative is that it enables you to operate the trolling motor with your foot, freeing your hands to throw a fishing rod.

Because of this significant benefit of foot pedals, the vast majority of fishermen choose trolling motors that are operated by foot pedals as opposed to those that are handled by hand. Take a look at the bass pro circuit; these days, almost every bass professional employs a trolling motor that can be operated with the foot.