All things being equal except for rocker, are there any sea conditions where more rocker is faster than less rocker in a sea kayak? Looking for opinions.
Rocker and speed
Regarding speed rocker has little to do with it. It is all wetted surface and waterline length. Having said that, the shape of the hull and the manner in which it gains volume contribute significantly to speed.
Yes
More rocker makes you much faster when you have to turn a lot. Also more rocker could be better in just the right kind of wave conditions.
Less rocker is fastest in straight paddling in flat water.
I always wonder why folks want to know what kind of boat is fastest, because it rarely matters. You can only paddle your fastest for about 15 or 20 minutes and most of us paddle for much longer than that.
What is more important is what boat paddles the easiest at the speed you want to go.
For me the question would be like this:
I’m 230 and 5’10" of average build. What boat would paddle easiest at about 4 mph (with a total load of 250 pounds) and still be able to handle some rough stuff and surf.
I’d get more useful information this way since I’m not a sprint racer…or any other kind of racer for that matter.
back at ya
FrankNC wrote: “I always wonder why folks want to know what kind of boat is fastest, because it rarely matters.”
Hmm, that’s strange. For myself, I often wonder why other people wonder why people ask the questions they do. It seldom matters.
Maybe we’re all just curious cats, seeking our deaths in different ways.
agreed
theoretical understanding is very interesting
I think that absolute speed matters less
than finding a boat that is a good match for our paddling style and effort. Sometimes a boat that is a poor bet in a race is easy to paddle at a good speed on an everyday basis.
That’s what I was trying to express
Top speed is rarely important. Ease of paddling a cruising speed is really important.
Paddling in heavy, confused seas
You will make much better progress with a boat with some decent rocker in the bow. A boat with no rocker will plow into the waves and won’t let you dance with the haystacks. Too much rocker will slow you down.
I’m talking reflecting waves and haystacks, short period storm surf etc.
Confused Seas?
Confused paddlers maybe, but no such thing as confused seas.
kinda like frightened lightning
Good point, although it is a standard term with a well-recognized meaning. I think I’ll keep using it, but also try to add to the language “frightened lightning” and “capsized wave” (“what, i didn’t capsize, it was the damn wave i was riding that capsized”)
frightened lightning…
My Uncle’s brother’s son was struck by thunder once!
In rough conditions
a kayak with greater rocker will allow you to put more of your paddling effort into forward propulsion because it is effected less by the waves. A stronger tracking kayak will be pushed around by the waves more and take more correction strokes to stay on course.
Pendant
Pendant, n.
One who, by correcting others, gives himself (or herself) just enough rope by which to hang. …done with the unnecessary need to be meticulously accurate when communicating completely mundane things. May be done with the intent of making others feel inferiorâ¦and/or himself superior, part of role-playing, humour, being an idiot, (trying to) showing off how smart you are, and as mentioned an unnecessary need to be meticulously accurate.
The problem for me is
that you can’t have all things equal except for rocker in the first place.
If you keep the overall boat length constant, it will shorten the water line length which has a direct impact on the top speed. It will also affect the location of the paddler relative to the water as the boat will have more draft near the center of gravity. This might change the paddle length needed and the overall reach of the paddler which might affect his power and his optimal cadence.
You could fix the waterline length and essentially add on to the existing boat so that it has more rocker, but the portion of the hull in the water remains the same. This would add weight and potentially change the way the boat behaves in waves and wind as well as how it turns using a lean.
With ideal flatwater conditions, with no turning, rocker really has no value as the portion of the kayak poking up and never touching the water just adds dead weight. When you consider the rocking motion from the strokes you might add a little rocker, but it really comes into play in the wind and waves (or leaned turns). That’s the only time that part of the boat is actually in the water, so that’s when it’s really doing something for the paddler.
I don’t know the pedigree of racing designs, but I would imaging that unless the conditions or parameters are different for the races mentioned, the portion of the hull that is actually in the water would be similar for the kayak and the canoe.
jim
Agree, except for the part about…
… rocker not having use in flat water racing. Look at most K1 designs, particularly the current state of the art. Some have a surprising amount of of rocker, to folks who have an sea kayaker’s/marketing blurb understanding of rocker and expect fast to be flat anyway…
Since you specified “in a sea kayak”…
I should add a bit to keep any of my other comments in context:
For sea kayaks, the “flat is faster and curved is slower” is largely a marketing convenience. An oversimplification that holds true more than not with typical/average/common sea kayak designs, so is taken as being “true” for many.
Of course most sea kayak designs follow along pretty similar lines/previous examples. More importantly their designs are more art than science. Also, they are mostly divided between “expedition”/“touring” types (generally less rocker) or “day”/“play” types (generally more rocker) which further cements this limited type of understanding of rocker.
The handling aspect is also an oversimplification and dependent on a LOT of variables, but for sea kayaks this also tends to works that way more often than not for similar reasons.
So… for SEA kayak SHOPPERS, the oversimplification works as intended and doesn’t really cause any grief (until someone wants to go beyond that level of understanding but still wants to cling to these precepts…).
The real answer to all this: It depends.
Pendant or pedant?
While a pendant hangs around ones neck and may be the instrument of hanging oneself physically I would think that pedant is the noun to choose here for hanging oneself intellectually.
Pedantically
Stephen
PS… if rocker allows you to paddle harder in certain conditions it is faster. Also a more rockered hull can typically have a higher seating position for the same CG and allow a more vertical stroke that interferes with the front deck less which may be a faster paddling position.
John Winter addresses this
in the “Effects of deadwood” section of the following article:
http://www.greenval.com/shape_part1.html
He addresses the question in terms of both general hull design and specific paddling conditions (he’s talking about canoes but I would assume at least some application to sea kayaks).
Confused seas
are waves coming from differing directions, resulting in waves that are irregular and unpredictable.
Well said Frank!