Why motorize your kayak, and do you really need a motor on board?
What type of solution would best fit your kayak motorizing needs – an electric trolling motor, or an outboard gas engine? How to motorize your Wavewalk® kayak on a budget? What are the practices we recommend following in a kayak motorizing project?
This section of our blog is dedicated to answering these questions, and others.
What about a car-top boat that paddles very well?
And what if you actually need a trailer-free, ultra-lightweight, two-person fishing boat that’s easier to paddle than a kayak? Check out our 700 Series »
We classify the new, patented Wavewalk® 700 series as a two-person, car-top fishing boat (microskiff) because it offers enough room and load capacity for two anglers, and stability that’s on par with the stability offered by motorboats such as Jon boats and dinghies.
Common SOT and Sit-in fishing kayaks, including the biggest and widest ones, are prevented from providing such stability because of their monohull design, which is the primary reason why they cannot be driven with powerful outboard gas motors.
However, Wavewalk’s car-top boats from the 700 series are just 31″ wide, and they are much easier to paddle and more comfortable than SOT and Sit-In fishing kayaks are. Learn more »
The 500 Wavewalk® Kayak Series
Kayaks from the 500 are smaller than car-top boats from the 700 series. They can be outfitted with smaller, less powerful outboard gas motors, and carry less load.
Here is an example of a Wavewalk® 500 model outfitted with a 2HP outboard gas engine and a pair of inflatable side flotation modules, driven in choppy water at Horseneck Beach, Massachusetts –
This video demonstrates the high-capacity inflatable tube flotation, detachable spray shield and motor mount that turn this W500 fishing kayak into a small, high performance, motorized fishing kayak:
Why Motorize Your Kayak?
A motor adds to your kayak’s speed and range of operation. In certain situations, this can make the difference between being able to come back home, and staying out on the water, or beaching far from where you had launched from. That is to say that a motor can add an element of safety to your kayak fishing or touring experience.
Another consideration is that a motor can make life easier, if you don’t feel like paddling, or in case you’re not capable of paddling where you want to go.
If you’re fishing from a kayak, a motor can be useful for trolling, and for quickly skipping from one fishing spot to another.
Electric Trolling Motor or Outboard Gas Engine?
If you don’t own a Wavewalk® kayak, you may as well skip this section, since other kayaks are not suitable for outboard gas engines, and they can accommodate only weaker, electric motor systems that are commonly know as trolling motors, because they typically involve going at low speed, and generally on flat water.
However, if you own a W500 kayak and you’re looking to motorize it, you’re facing the problem of choosing between an electric power system, and an outboard gas engine.
Before going further, we’d like to clarify a number of things about outboard gas engines:
First of all, we don’t recommend using an outboard motor that’s rated above 2.5hp with a Wavewalk kayak from the 500 series, simply because there’s no need for more, in our opinion, and we think that a stronger motor might overpower the kayak, which is hazardous.
Second, when we refer to outboard gas engines, we mean 4-Cycle (4 stroke) motors that are cleaner, quieter, and easier to operate than the old, 2 stroke motors that require mixing oil in the fuel.
Third, we recommend using an outboard gas engine with a 20″ (long) shaft, and not a 15″ (short) shaft.
What are the drawbacks of outboard gas engines?
The most obvious is that they are noisy, while electric motors are quiet.
As far as fumes and ease of operation, the new 4-cycle motors are as clean and easy to operate as electric motors are: No fumes, no need to mix oil in the fuel, and starting them is easy.
Weight: The 2hp 4-cycle Honda outboard gas engine weighs 28lbs. It’s heavier than some small or expensive electric motor systems, but considerably lighter than others that can weigh up to 80lbs. In any case, at this weight you can lift the propeller out of the water and paddle your W500 without feeling much of a difference in performance. You can drag the kayak on the beach, and you can even car top it.
Price wise, a new 4-cycle outboard gas engine can cost between $500 and $1,500, while an electric trolling motor system can cost between $250 and $1,500.
Maintenance: Outboard gas engines require some maintenance while electric motor systems are almost maintenance free, but the new, 4-cycle motors are much easier to maintain than the old 2-cycle ones, so this is not necessarily a big disadvantage.
Some areas are restricted to motorboats, but not to ones that are powered by electric motors.
What are the drawbacks of electric trolling motors?
There’s a much broader choice of electric trolling motor systems on the market today, which means there are numerous advantages and disadvantages to consider.
The most common disadvantage in electric trolling motors is their limited range and speed, and the two are closely linked to each other. Gas motors offer unlimited mileage at high speed, since you can take plenty of extra fuel on board in a can. This is not the case with electric systems that depend on batteries that are either very heavy (too heavy to carry more than one on board at a time), or very expensive. Going at full speed with an electric trolling motor, even a weak one (30-40 lbs thrust) can drain your battery pretty quickly, even if it’s an expensive high-tech battery. This leaves you with a choice of a weaker electric motor, and consequently reduced speed.
When evaluating the potential of an electric trolling motor, you need to remember that going at full power instead of half power would never double your speed (in fact, in some cases the effect of adding power may be hard to notice…) but it would surely drain your battery at half time. You also need to bear in mind that both water and weather conditions often require using more than a fraction of your electric motor systems’ capacity, because the real world is not an ideal one. Knowing this, you need to view electric trolling motors data as representing perfect world situations that have partial, or little relevance to real-life situations in which you could, and eventually would find yourself on the water.
Weight: A standard, deep cycle marine battery can weigh between 40-60lbs. That’s a lot for a small, car top boat such as the W500 kayak. On top of this, the motor itself adds weight, so the entire electric trolling motor system can weigh more than the kayak itself, which is counter productive and problematic. For example: If your heavy, deep cycle marine battery runs out of juice far from your starting point, you’d need to paddle your kayak back with an additional heavy load on board – It’s a point worth consideration, especially if you imagine going against a tidal current, and/or strong wind, while being tired after a long kayak fishing or touring trip.
Price: A battery, cheap electric motor and charger can be yours for less than $250. This is a good deal, but you’ll pay the price in high weight and low speed. At the other end of the spectrum, a computerized electric trolling motor system with integrated GPS would cost you over $1,500, and although it will be lighter than an outboard gas engine, it would still offer less speed and a smaller range of travel.
Maintenance: While electric motors are practically maintenance free, their batteries need recharging, which takes both time and a power outlet that might not always be available to you.
Thrust, Horsepower (HP) and Kilowatts (KW)
People outfit their W500 kayaks with electric trolling motors ranging between 25-70 lbs thrust, with the typical range being 30-50 lbs thrust.
As for outboard gas motors, the range for W500 kayaks goes from 2 HP to 4 HP, with the typical unit being a long shaft 2.3 HP motor.
We recommend not to overpower your W kayak, as doing so may be hazardous.
Kilowatts and Horsepower
- 1 KW = 1.34 HP
- 1 HP = 0.745 KW
This basic information could be useful when you read electric motor specs…
Conclusion? -Between outboard gas engines and electric trolling motors there is no winner or loser, and it’s up to you to systematically weigh the pros and cons, relatively to your touring, camping and fishing needs, as well as your carrying capabilities, and last but not least – your budget.
Tip I: If you’re thinking long trips, camping, moving water and tandem – think outboard gas engine. If you’re thinking short trips, flat water and lighter loads, think electric trolling motor. Needless to say that more power equals more fun, but too much speed could be hazardous.
Tip II: Whether you choose to outfit your kayak with an electric motor or a gas outboard engine, if you’re planning to take your W kayak in saltwater, make sure the motor is rated for saltwater.
Motor Kayak Recovery
Whether you motorize your kayak with an outboard gas engine or an electric trolling motor, you’d need to take into consideration the extra weight, and consequently add flotation to your kayak, so that you may be able to recover it case of an accident. Read more about flotation »
How To Motorize Your W500 Kayak On A budget?
The number of options and price range of small outboard gas engines is limited, which makes it easier to decide. The choice of motors for the W700 series is much broader.
As for electric trolling motors, you can find inexpensive ones online and in stores, and the same is true for batteries and chargers, although buying a battery online doesn’t make much sense due to the high cost of shipping – unless the battery is shipped free, for store pickup.
Side Mount or Transom Mount?
It’s possible to mount a small, lightweight gas outboard on the side of the W500, as demonstrated here » But due to their weight and power, we recommend mounting such motors at the back of the W500 kayak cockpit, using a transom mount. In this position, steering is made easy by the use of a long, articulated (U-jointed) tiller extension.
As for electric trolling motors, being lighter, they can be mounted either at the back of the cockpit (transom mount), or on its side.
Some of the more expensive electric motor systems come with a kayak mount, but we recommend you double-check if the mount is compatible with the W500 kayak – Chances are that it is not.
Short Propeller Shaft or Long Shaft?
20″ Long (L) propeller shaft outboard motors fit both the W500 and W700 series perfectly, and these are the motors that we recommend using.
As for short (typically 15″) shaft motors, they don’t perform well with Wavewalk® kayaks and boats, and we do not recommend using them. This is true both for electric and gas motors.
The 20″ distance is measured from the inner top side of the motor’s clamp bracket to the horizontal ventilation plate located above the propeller.
Any motor, whether electric or gas, whose propeller shaft is shorter than 20″ is not recommended for use with Wavewalk® kayaks or portable boats.
Accessories For Motorized Kayaks
Wavewalk offers 2 models of transom motors mounts for its 500 series –
- The TMM 20 fits 20″ long (L) propeller shaft motors
- The new TMM 20-15 fits 20″ long (L) propeller shaft motors
high volume DETACHABLE inflatable flotation modules
DETACHABLE transparent spray shield
Overpowering your motorized fishing kayak
Overpowering a kayak or a boat can be hazardous, and result in accidents, which is why we recommend not to do it.
The following article discusses various aspects of overpowering, and features a video of a W500 powered by a 6 hp outboard motor »
Important SAFETY ADVICE
For users of Wavewalk’s motor mounts from all models: Before going on a motorized trip, verify that the wide wooden bolt knobs that secure the Wavewalk® motor mount to the kayak are safely tightened to the maximum. Failing to tighten the bolt knobs could result in unwanted vibrations and noise. If you feel such unusual vibrations and/or hear unusual noise, stop the motor, turn around, and tighten the bolt knobs to the max.
Driving with loose bolt knobs is hazardous, similarly to driving with the motor’s clamp screws loose, and it could result in an accident.
Adding a pair of 5/16″ nuts would lock the knobs in place, and prevent them from getting loose.
Never operate the motor without the motor’s stop switch (“kill-switch”) attached to your arm.
For motor operation and maintenance please refer to your motor’s owner’s manual.