Design/ speed question

I am on the slow path towards kayak building. I still have far too many jobs to finish up for me to start a new one, but I have bought and am reading about 12 books of building kayaks and have a general idea of what is done to create certain attributes of different kinds of purposes in the water.

One thing that is universal to all movement and maintenance of speed, (no matter what the machine is) is the fact that speed is a function of input power VS resistance. Be it cars, aircraft, boats, wagons, chariots, running on legs or worms crawling. It’s ALWAYS a matter of input power VS resistance.

Engineers have struggles with these realities for centuries. The idea is very simple. The variables on the other hand get very VERY complex.

And all variables have limits. In engine powered machines a more powerful engine is often looked at. But you can’t simply make an engine larger and larger because larger means more weight for both engine and for what ever housing it is placed inside. Also a larger (meaning heavier) fuel tank also housed in a larger heavier frame. So more power moving more weight often give you the same power to weight ratio, gaining you nothing but loosing you money.

So more power coming from a lighter engine is the focus in many cases. But that produces a whole new set of problems, 1st among them being a cooling system to harness more power without making a larger heat sink. It’s easy to make a very powerful engine that weight very little but it last about 45 minutes before it destroys itself. Some race cars go all-out for second and the engine is rebuilt after every run.

In kayaks we can’t simply make them longer and longer because with length comes weight, and also the realization that at some point you can’t turn such a paddle craft in a practical way. That’s why you can’t buy a 36 foot kayak. And would not if you could. Who is powerful enough to paddle it faster then an 18 foot kayak? No one!
A “more powerful engine” would be a normal size man who would have to be 2X or 3X stronger then any other man. Or if you had a very long kayak that could hold a 600-700 pound man the weight of that man would requite enough surface to float him, meaning a lot more resistance going directly against the man’s power even if he is 3 times stronger than a normal size man. If you end up with the same power to weight ratio there is no advantage gained.

So the reality is that design factors are interesting to discus and hash around, but there is no formula existing to make a perfect kayak for all people, and probably not even for 1 person. Perfection, if it could be attainable for a certain paddler would come off that point of perfection as soon an any one thing was changed (like water surface, wind direction, weight inside the kayak, shifting that weight fore or aft, and about 100 more things that can change and effect not just the kayak but also the paddler.

Remember the paddler is the engine.

If we make 500 cars or airplanes and placed 500 different engines in them (all of which can vary in power, stroke, weight and fuel consumption,) how would we make up an accurate spec sheet?

How “fast” is that model of car or the airplane?

So all kayak makers are unable to give exact information on exactly what speeds and capabilities will be . Think of cars being sold with no engines. You buy one and put in the engine you have at home. Do you think Ford or Dodge or Chevy could tell you how fast it’s going to be?

And speed is just one of several performance factors. There are several others.

Capacity for weight carrying. (Paddler + weight of cargo)

Turning ability.

Overall weight.

Ability to edge and/or roll.

Ease of entry and exit.




And probably 10 others I have not thought of at the time of this writing.

I am too young in the sport to know how to speak well to the answers to these design questions.

But I am well educated enough to see the QUESTIONS clearly. And for all of them I see I expect there are still some I have not yet seen.

But learning is part of the fun for me.

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Very wise, and applicable to questions far beyond boat design. Beware of simplistic black and white answers. The world is mostly gray.

Steve, 21 feet does seem to be the longest kayak one human power can power. Westside tried a 24 foot X-Par Missile, but I have never met anyone who could really make it work.

Olympic boats, at 17 feet, are faster than most 21 foot boats, but therein falls the comfort scale. Olympic boats are not comfortable and take incredible amounts of concentration.

21 foot boat are also almost all about straight line speed, they usually don’t turn because their keel is kept flat, no rocker.

I opted for a 19 foot racer because it does turn, some, That makes me faster in technical areas and top speed is still about the paddler.

The next biggest thing in performance is cockpit placement. Recreational boats have the cockpit set at 54 percent of the boat, from the bow. That makes the stern sink a little when you try hard to make it move. That forces it to climb the bow wave, limiting speed.

If you have any speed questions feel free to contact me. Others will know more about carrying capacity, rolling, and so on. The boats I have built are mainly race oriented, except for the Pck boats for my better half and I.


I’d love to take you up on that offer Craig. I have yet to do ANY building but I am reading what I can find on the subject. I have a firm understanding of the difference between a symmetrical, a fish form and a Danish hull, but none of the books I have here have gone into the hydro-dynamics of form. Only how to make them. Rocker and keels are easy to understand and after using several kayaks of different shapes I have some tactile understanding of it too, but the blending of the above 3 shapes and combining each one to some degree with less of more rocker is a bit confusing.
All the kayaks I’d make would probably be for touring and for use in choppy water. Racers would have little use to anyone around here. A windless day is rare and a normal day is going to have 10-15 MPH winds so maneuvering is going to be more important then speed. Not that speed is unimportant, but simply less so then turning abilities.

An advantage of building skin on frame kayaks is that you can tweak the design before the final skinning. Wrapping the frame with clear stretch wrap (the stuff they use to wrap pallets of goods) allows the builder to test paddle the boat before committing to completion. If you build it using pegs and tied connections (with synthetic sinew) the frame can be partially dissembled and modified until the characteristics you seek are achieved.

Yes I am aware of that fact Willow. In 2 books I have on skin-on-frame building that fact is mentioned and it’s a wonderful idea. The down side is that copying a SOF kayak to strip built doesn’t go over “one to one” because the Strip Built kayak is heavier and trims a bit different due to it’s bulkheads which are absent in the SOF hull. Ambercomby told be it will get you close, but the only way to fine tune a wood kayak is to make it from wood.

I think I’d REALLY enjoy doing a lot of different kayaks and testing them, but at my age and without being a wealthy man I am not certain the cards hold that kind of future for me. I’ll just have to do all I can do,until I can’t anymore.

But one trick you can also use is to substitute saran wrap for a trial test. Not very good for performance because you can’t get a very slick wrap with it, and of course it’s far from a tough skin, but to see if you have a workable design and to do some basic testing with wider, narrower or differing profiles or different rockers, it works.

(again, according to what I have read. What I know for a fact about building as of this writing is zero, zilch, nada, zip 1 less then 1. )

I built 2 stitch and glue boats from plans. Interesting and I learned a lot about every aspect from selecting materials, cutting the pieces , assembling them , and using glass cloth and epoxy .
It was not expensive compared to buying a composite boat.

AI has come up with a solution for the problem of plasma instability in fusion reactions. It might be able to solve these problems too. :thinking: :wink:

Enjoy your time and effort on the water and “Paddle On”.

Get in the boat and paddle it.

Practice your forward stroke and torso rotation. When I first started paddling (2 years ago), my avg speed was 2mph to 3.

I now average regularly at 4mph even on windy days and choppy waters. I avg 3.8mph in 18mph wind (26mph gust) in an 10.4 mile paddle yesterday. A year ago I could barely move in this kind of wind. I am just an average overweight middle age person. I practice a lot and asked questions on here and got good feedbacks.

I have changed boats 4 times from the following

Boreal Design Alvik 17ft
Current Designs Solstice Gts 18ft
Necky Chatham 18
Zegul Greenland 17ft9”

The change in boat didn’t make me go faster but the practice in paddle strokes did. Changing paddle from a low angle Werner Cyprus paddle to a fat Werner Ikelos helped a nudge. I am trying to stay consistent at a relaxed 4.5mph average. I may never get there but having fun to improve my techniques.


I had someone film my paddling stroke 10 months ago in this video. Watching this again today, I have more torso rotations and today I drive with my leg and hip. It’s quite a boring video to watch and not meant instructional. I posted here asking for feedbacks then and got good inputs.

In the video is the Necky Chatham 18 which is a very fast kayak but i couldn’t drive it faster than.


You might want to consider signing up for one of the kayak skills camps that are offered around the country (many under the aegis of QajaqUSA.) I’ve been attending them regularly since 2017 and besides being fun and getting great one-on-one instruction from some wonderful coaches, a lot of the attendees are happy to let others test paddle their boats and any QajaqUSA sanctioned events include organization-owned loaner boats and paddles. The events I’ve been to have always had from 50 to 100 assorted craft, including homebuilt skin on frame and strip built, and conventional plastic and composite kayaks. Pics from the August camp in Frankfort Michigan and the October DelMarVa camp in Delaware.


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Oh I sometimes lay awake at night dreaming about going to such events. If I live that long, someday I will. I would prefer to go to one (if they exist) on Lake Superior simply because it’s closest.
But it’s likely I will not be able to go to any such events for at least 2 more years. Still too much work for me to do before I can justify making my customers wait even longer than they already have.

The events are only 3 or 4 days (Thursday through Sunday) and the Michigan one the last weekend in August, when (in my experience after 40 years in contracting) most customers are more concerned with their own end-of-summer leisure activities than being pushy about deadlines.

I follow the Inland Sea Kayakers group on Facebook and they post notices of training and paddling rendezvous in the upper Midwest regularly. If I spot anything that is based on Superior, I’ll relay it to you.

We used to have a paddling “regatta” at a large local lake in my area where the same on-water test paddling option was usually available, both in boats that attendees brought or demo boats that vendors brought to the event. That has not been revived since the covid years but may resume. We do still have one for solo canoeists. Might be something similar nearer to you.

I have also been on group day paddle outings where other folks didn’t mind swapping boats and/or paddles with me so we could both see what the other models were like. (Though I usually don’t profit as much from that experience as they do since I tend to be in the higher performing kayak.)

It’s taken me 22 years to “curate” my fleet of boats (a process that included trading several up, testing many models and the serendipity of stumbling on incredible deals on some very cool ones when I wasn’t even looking. ) I have a range of them for various waters and conditions. When I think about downsizing the armada, I can’t pick since they are all unique in one way or another. There will be a hell of an estate sale when I’ve paddled my last.


Steve, you go through more boats than you can shake a stick at. The advantage of one boat is thst you can learn the nuances. You become so dialed in to that boat you can test different techniques and see whst works best. Look at how far you came with your Chatham.

Thanks so much Willowleaf. I’d love to know what’s up-coming. I don’t think I can go soon, but hey…maybe I could break free if I knew there was something specific to “break free to”

Jyak (Above) is correct in that I have bought and sold a lot of kayaks in the few years sense I have become a kayaker. Over 30 now. However even thought I have tried most of them, they were bought with the specific reason to be re-sold here in Wyoming so I can create a small groups of other kayakers. Wyoming, which seems to be the last place to find a group of sea-kayakers.
So John, you are correct in learning 1 kayak. I have not just falling in love with one, but in the 34 (I think it’s now 34…or something close to that number) I have had, only 2 of that number were kayaks I decided to keep and then changed my mind about. By far, the one I have the most time inside is the Chatham17. The long 18-1/2’ P&H was one I thought 'd keep until I found I could not store it and having no funds at the time to get a larger shed I only kept it for about 2 weeks. Also my wife just sold her Prijon Yukon 2 weeks ago.

One that I got last year which I am pretty sure is going to be a “keeper” for me is the Eddyline Fathom. I also really like the Sea Lion Shadow, but if a friend decided he wants it may turn it loose now that I have the Chatham17 and the Fathom. That Shadow is good enough that if no one ever wanted to buy it I am 100% OK with just keeping it. But having 3 means Anna and I can take out a friend too, and 3 seems to be a minimum.
If I strike a jackpot and buy or build a larger kayak shed, maybe I’d be OK in the future with keeping 4 or 5, but for now 3 is a good number of Sea kayaks. We also keep the 2 Old Town Loons for the days we want to just go paddle around and take a picnic with us or hide in the reeds and brush on the river to watch deer and birds. We started with the 2 loons and even though I have become far more interested in Sea Kayaks, I have to admit the way the loon handles and how easy it is to use had made both Anna and decide they are not for sale. There are just times when 2 rec kayaks are very nice toys to own and we use them fairly often.

I was feeling bad because I have 2 and have been looking at the next one. In total, less than a dozen.
You have made me feel better since I plan to try it Monday.

So many of us started with an OT Loon or something quite like it. My local paddle shop owner says they remain his top seller. Glad you still enjoy yours.