We wanted to show the Wavewalk S4 going in rough water, but since we couldn’t find water that was choppy enough in Key Largo, we made our own chop 😀 Larry drove his commercial fishing boat, the Line Dancer, Orit sat at the stern and shot video with our new Nikon camera equipped with a X83 optical zoom lens (great camera), and I drove an S4 in the boat’s wake.
The Line Dancer’s wake was V shaped, with pronounced “ridges” of waves and turbulence on both sides, and a quieter area in between. When we went in open areas where the tidal current and wind created natural chop, adding the boat’s wake on top generated pretty hectic conditions that were a bit challenging to drive through, mainly because the motor on my S4 was a little 3.5 HP that didn’t allow for much planing and playing. This application calls for a more powerful motor, and a 6 HP outboard would have probably yielded more spectacular action shots. But at least we were able to demonstrate the principle… When we drove in quieter zones, I just surfed the Line Dancer’s wake, and that was easy and fun.
What’s the real-world advantage of the S4’s ability to go through fast currents and chop? “Real World” usually means you have to go from point A to point B, and you’re not just looking for some driving action fun. This can happen when you use the S4 as a tender for a bigger boat, or yacht, or when you drive in fast rivers that are swollen by water from melting snow in spring, or by tidal currents in coastal areas. Jon boats and skiffs don’t excel in such conditions, to say the least, and inflatable dinghies are neither the most comfortable nor the most reliable choice. But the S4 shines in the chop, not just due to its natural, physical, “catamaran” stability, but also because it offers the driver to ride a saddle seat similar to the seat that other high performance vehicles feature, such as personal watercraft (PWC a.k.a. “jet ski”), all-terrain vehicles (ATV), snowmobiles, and dirt bikes.
I created a custom trailer for “The Dub” [Wavewalk S4] out of an old sailboat trailer. We took it to a local boat ramp and motored about an hour through the marshes to a barrier island to go shelling. Made it there and back in fine style.
We got some funny looks from people watching us go by and watching me launch the boat with one finger!
Wavewalk S4 driven in choppy blue water in the Atlantic ocean close to Key Largo, Florida. It was fun to drive this watercraft that seems to be almost immune to waves, wherever they come from. Hopping on waves and making sharp turns was easy solo and with a passenger on board.
As a skiff, it’s extremely seaworthy, and as a kayak it’s anything but 😀
We towed it behind the mother ship, and it was a pleasure to watch how well it behaved… It can serve as a perfect boat tender for a big boat or a yacht – It’s seaworthy, comfortable, fun to drive and to paddle, can be beached anywhere, and it can carry up to three people on board.
The S4 in this movie is under powered by a 3.5 HP outboard motor – A 6 HP outboard would have worked better in this case, but still, driving this ultralight microskiff in the chop was a lot of fun. Thankfully, the S4 is not a solo skiff, and driving it with a charming passenger on board was even more fun.
We didn’t have to outfit it with a spray shield, as hardly any spray got it.
Fin lives next to the ocean, and he loves fishing in shallow water. He’s been fishing out of an 18 ft skiff, but being a big boat with a heavy motor, that skiff drafts 18″, which is less than optimal for shallow water, especially at low tide, when the risk of getting stranded increases. Fin and his family also didn’t like how their big skiff felt in choppy water, and how it reacted to other boats’ wakes. Fin ordered an S4 with the intention of having it replace his 18 ft skiff. After he and his wife tested their S4, they decided to sell their skiff. The S4 will also replaces their tandem kayak. Says Fin: –
The video where I slide it down the ramp is the very first time trying it out. The young guy on the boat is my youngest son Adam. He is a student and he was excited beforehand. Then he loved testing it out.
The videos are all at less than 1/2 throttle as we follow the 3.5 hp Tohatsu engine break-in procedure.
The S4 also lets us explore all the coastal islands where previously we could only take a kayak.
One question we had was the best position for the engine tilt. It looks like it has 5 holes for tilt and it came in the center hole. Any advice for that?
Here are the first pictures and videos. All unedited happiness.
Another important trade-off that you should be aware of is related to propellers: High pitch propellers are designed to deliver more speed and less torque (thrust, push force), and they work best with lightweight boats such as the S4, while low pitch propellers are designed to move bigger and heavier boats at lower speeds, but they should not be used with lightweight boats such as the S4, since they might make the motor run at a too-high RPM.
Outboard motors manufacturers’ websites say that (quote) “UNDER NO CIRCUMSTANCES SHOULD YOU EVER USE A PROP WHICH WILL ALLOW YOUR OUTBOARD TO OPERATE ABOVE THE OUTBOARD’S RECOMMENDED MAXIMUM RPMs“. This means that you should avoid using propellers designed for use with very heavy boats, namely propellers in the low-pitch range.
Note that 20″ long (L) propeller shaft motors typically ship with propellers that are not necessarily optimal for very lightweight boats such as the S4. For example, the 6 HP 20” long (L) outboard from Tohatsu often comes with a medium range 8 pitch propeller, which is fine, but mounted on the S4, such a motor could drive the S4 12% faster if outfitted with a 9 pitch propeller.
Propeller pitch information is available on outboard manufacturers’ websites.
Since the S4 is a very lightweight boat, you should preferably outfit the outboard motor for it with the highest pitch propeller available for it.
Diameter – Don’t try to use a propeller from a small outboard with a bigger outboard, or vice versa.
SMALL PORTABLE OUTBOARD MOTORS
For the S4, small size means a highly portable but under-powered outboard motor.
2 HP outboards
Outboard motors in this class weigh around 30 lbs, which makes them fully portable even for a user who’s not very strong. A 2 HP motor can propel an S4 skiff with one person on board at speeds up 8 mph, even in choppy water. This speed would decrease as the boat is required to carry more passengers on board. S4 owners who tested such motors with their S4 skiff reported that the boat felt under powered, which means that they felt like going faster, but the motor lacked the power required for this. For this reason 2 HP motors are not popular with S4 users. Another reason for their lack of popularity is the fact that being air cooled makes these small motors noisier than bigger, water cooled motors.
Propeller pitch – The Honda 2.3 HP comes with a 4.75 pitch propeller
MEDIUM SIZE PORTABLE OUTBOARD MOTORS
For the S4, a medium size outboard motor means powerful enough but still portable. Motors in this 3.5 HP to 6 HP range are the ones we recommend for most users.
3.5 HP outboards
Outboard motors in this range weigh around 40 lbs, which makes them still portable, but less so than 2 HP motors. A 3.5 HP motor can propel an S4 skiff with one person on board at speeds up to 11 mph, even in choppy water, and it can propel the boat at 8 mph with three passengers on board in moving water. This size motor is popular among S4 and W700 users, as it offers a good trade-off between power and weight for people who must lift the motor or carry it by hand over long distances. These motors are also less expensive than bigger ones.
Propeller pitch – For their 3.5 HP motor, Tohatsu recommends either the 7 pitch (Plastic) or 6 pitch (aluminum) propellers, for lightweight boats such as the S4 (under 500 lbs). We say get the 7 pitch propeller, unless you think that you need the more durable aluminum propeller.
6 HP outboards
Outboard motors in this range weigh around 60 lbs, which makes them portable only over short distances, and not for everyone. A 6 HP motor can propel an S4 skiff with one person on board at 17 mph, and it can propel the boat at 12 mph with three passengers on board. 6 HP is the second most popular motor size among S4 users.
Propeller pitch For their 6 HP outboard used with lightweight boats up to 500 lbs (such as the S4), Tohatsu recommends their 9 pitch propeller. The 8 pitch propeller would work too, especially if you intend to have the boat fully loaded, so that it would weigh over 500 lbs in total.
BIGGER OUTBOARD MOTORS
8 HP to 10 HP outboard motors are too heavy to be carried by hand, and they may be too powerful for inexperienced drivers to use safely. However, some of them come with electric start instead on manual start, which is a nice feature. They also come with an alternator that can serve to power small electric devices on board.
8 HP outboards
Outboard motors in this class weigh between 65 and 80 lbs. At such weight, these motors can no longer be considered as portable, and the main reason to use them is the fact that are offered with electric ignition, which eliminates the need to start them by pulling a cord. People who like driving at high speed may prefer these motors to less powerful ones. The S4 outfitted with an 8 HP motor performs well in choppy water, but it could feel over powered for an inexperienced driver, which should avoid using such motors with their S4. Heavy users may benefit from driving with a U-jointed tiller extension, in order to move some weight forward from the stern towards the middle of the boat.
Note that these bigger motors don’t come with an integrated fuel tank, but this isn’t necessarily a problem, since external fuel tanks can fit inside the S4’s hulls.
9.8 HP and 9.9 HP outboards
We tested the S4 with a 9.8 HP Tohatsu and a 9.9 HP Yamaha outboard, and it worked well. Practically, this class of heavier and more powerful motors offers no advantage over smaller motors unless you’re a speed fan, and you’re also capable of driving small boats safely at such speeds. To those who want to take the risk of overpowering their S4 with such big motors, we recommend reinforcing the mounting plate.
This video shows an S4 powered by a 9.8 HP Tohatsu motor filmed from the deck of an S4 powered by a 5 HP Tohatsu motor:
Currently, the S4 is the world’s fastest designated kayak. The 17 mph kayak speed record was achieved by Captain Larry Jarboe, of Key Largo, Florida, in his S4 outfitted with a 9.8 HP Tohatsu outboard motor.
We recommend that inexperienced drivers avoid using high power motors with their S4. Instead, they should pick a motor within the 3.5 HP to 6 HP range.
OUTBOARD MOTOR BRANDS
After years of testing motors and getting input from our clients, we can recommend all Japanese brands, namely Honda, Suzuky, Tohatsu and Yamaha. Mercury is a Tohatsu brand, and the small, portable motors offered by Evinrude are made by Tohatsu. Motors from all these brands are good, and your decision about which motor to use with your S4 should be based on factors such as price, weight, features, availability, warranty, etc.
A kicker motor is a name given to any outboard gas motor used on a big boat for trolling, or as a spare motor, and for positioning and driving sailboats over short distances when sailing them is not possible. Being used on bigger boats, kickers often feature a 20″ long (L) shaft, which is the right size for the S4, but the propellers used with them are typically low-pitch models that are not optimal for lightweight boats such as the S4. If you buy a kicker, check its propeller, and if it’s not a model with the highest pitch that the manufacturer recommends for lightweight boats, replace it with such a propeller.
Mud motors feature a surface drive, and they offer a huge advantage to people who want to drive in very shallow water, mud, water with many underwater obstacles, and water with plenty of vegetation.
6.5 HP mud motors
Mud motors are bulkier and heavier than regular outboard motors. A 6.5 HP mud motor weighs around 80 lbs, and it’s not portable. The reasons you’d want to use such a motor instead of a regular outboard of similar power are if you need to go in very shallow water (skinny water) and mud, and if you fish or hunt in water with plenty of vegetation and underwater obstacles. The S4 performs very well with a such a mud motor. We do not recommend using less powerful mud motors because typically, these motors require more power than regular outboard motors do.
Electric outboard motors
Typically, electric trolling motors are not powerful, and they are designed to propel heavier boats than the S4 (e.g. bass boat, skiff, Jon boat) at a very low speed, namely trolling speed. This type of application requires high thrust (small pitch) propellers, and it’s also the reason why trolling motors are rated in thrust units (lbs) and not in horsepower (HP or KW) – When you buy such a motor, your primary interest is how big (heavy) a boat it can move, and not at what speed.
Some electric trolling motors are described by their manufacturers as “outboard motors”, namely comparable in performance to small outboard gas engines. If you’re interested in such electric motors, we recommend comparing apples to apples namely power units to power units, and not power to thrust, which is meaningless. Remember the laws of physics, and apply the formulae for Kilowatts to Horsepower conversion, which are: