Which factors affect speed the most?

I have two kayaks.

A CD Solstice SS. It is 17.5’ long, 22" wide, FG

A Necky Zoar Sport. It is 14’ long, 25" wide, PE

I can do 6 miles in 2 hours in the Solstice and 4 miles in the Zoar. That makes sense because the Solstice is longer, narrower, and stiffer; but what is the relative contributions of those three traits to it’s better speed?

I ask because I really can’t fit into the tiny cockpit of the Solstice and want to replace it. I would like something exactly like it, but with a bigger cockpit, but with used kayaks I am going to have to compromise. I am wondering which factors are the most important.

How big a hit would I take going from 22" to 24"? Or from FG to PE? etc. etc.

This won’t be complete, too many work days in a row.

Longer waterline is faster, overall length means nothing ie: long overhanging bow and stern may look pretty but if it’s above the water it adds nothing to the speed. Waterline beam (again what’s in the water is what counts) narrower generally is faster, there’s a line that once crossed (everyone’s balance is different) where if it’s too narrow you spend too much time bracing and that slows you down.

Going from 22" to 24" the wider boat will definitely be slower.

Generally a rigid hull will be faster than one that’s more limber all other factors being equal. So a glass boat is generally faster than a poly one that flexes with each stroke. Lighter weight is also faster, less water displaced.

Bill H.

ss to regular GT Solstice is 1 mph or less

Width effects a few things
such as drag on water with wider being slower with same paddle input. More width and deck height also affect paddle stroke forcing you to sweep more than forward stroke and eating away some efficiency as you go less on straight course. Pay heed also to seating posture between two hulls. Working to improve these will cost nothing but time.

Too simple.
Assuming everything else about hull design is exactly the same, the longer narrower boat should be faster, but in the real world everything else is not equal.

There is a lot more to compare than pure top speed in assessing the suitability of kayak design. Not the least of which is how the boat handles rough water. How the boat tracks, primary and secondary stability, bow buoyancy–so many factors to consider and they all need to be blended in the right proportions.

I have found that the only way to determine how well any boat will work for you is to put it into the water and paddle it. With some boats, it only takes a short demo to tell that it ain’t right. Some feel right from the first couple of stokes–yet others might take extensive paddling in all kinds of conditions to fully realize a superior design.

so your looking
looking for a larger cockpit boat but still want speed, correct? You don’t necessarily have to get a wider boat. Example, my 22 inch wide Valley Avocet RM has a MUCH smaller cockpit width wise compared to my QCC 700x yet the QCC is only 21 inches wide. You might even want to try a QCC 700X. I had to add about 3/4 of an inch of padding to each side of the seat to make a nice fit. Were my wider Avocet fits snugly with nothing added to the seat area.

As a comparison
I paddled my old CLC 17 last Sunday and did 7 miles in 1 1/2 hours. I’ve done the same distance in my 18’ 3" Artisan Millennium in 1 1/4 hours. I’m 64 years old, but am very fit and typically paddle for speed and distance.

Seat vs. Boat Width
I just moved into a Solstice GTS from a 21-inch wide kayak and note the same thing dc9mm talks about in a previous post. My seat in the 21-inch wide hull is wider than the seat in the Solstice GTS. I don’t know why or what can be done about it. In my case, the GTS seat seems just right, so I’m not worried about it. You might ask at your local kayak shop if there are any seat retrofits that will give you the extra room you want.


Current Designs
Makes a wide base seat. It adds 3/4" on each side below the combing as the legs going down to the hull curve wider. It does involve glass work.

I had said he paddler but
as others pointed out, same paddler. Not useful so it is gone.

As to between the two boats, there are two parts of speed. One is the work it takes to accelerate a boat to a certain speed and the other is the work it takes to keep it there.

It sounds like if you happen to find any stability curves, though with the death of Sea Kayaking magazine I don’t know who is doing them, you need to look at the effort to hold a speed once accelerated to it.