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PostPosted: Tue Feb 05, 2013 3:49 pm 
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Just for reference, I have been able to consistently paddle at around 11km/h (approx 6 knots) in the TRAK. A sustainable top speed should be around 12-13km/h on flatwater.


"Was that fast? I thought that was fast. Was that fast"? (Quote from Jodi Foster in "Maverick")


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PostPosted: Tue Feb 05, 2013 4:33 pm 
lord high faltbotmeister

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Just for reference, I don't personally know anyone who can sustain 6.5 knots /7.5 mph for more than a couple of minutes at most in normal sea kayaks (measured with GPS), although I have heard of people in epic 18x's and rapier 20’s who can do so in very calm water
Then again all the people I paddle with are pushing 50 from one direction or the other :D

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Pakboats Quest 135, Nautiraid Narak 460, 416 & K1 (sold my 550), First light 420, Feathercraft Wisper, Fujita Alpina AL-1 400, Incept k40 (for sale)
Non-folders: Cape Falcon F1. Beth sailing canoe, 2014 Hobie Adventure Island


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PostPosted: Tue Feb 05, 2013 9:18 pm 
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Ha, the only way this paddler is sustaining 6.5 knots is with a sail!

d

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PostPosted: Sat Feb 09, 2013 12:26 am 
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Hey guys (and girls),

Looks like I should re-evaluate the actual distance I paddled. I got the speed of <del>6</del> 4 knots from a <del>4km</del> 2.5km / 20minute paddle, paddling unloaded against a slowly rising tide. The speed might have been way off if my google maps measurement was not accurate. I have to say the conditions was rather mild so it probably made it easier to paddle.

I'll be doing a one day, 80km paddle with a friend at the end of April 2013, so that will be a more accurate gauge for the TRAK (and the Folbot Cooper). Will keep you posted on the more accurate measurement!

The top speed of <del>12-13km</del> 9km per hour estimation was based on that <del>4km</del> 2.5km / 20 minutes paddle as well. I wouldn't say it's sustainable for 12 hours of expedition, but I think it's definitely possible for 20-30 minutes of paddling at that speed.

Edit: The correct distance covered should be 2.5km, and not 4km as originally mentioned. This has been updated in both the earlier post and in this post.


Last edited by Tak on Sat Feb 09, 2013 1:02 am, edited 5 times in total.

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PostPosted: Sat Feb 09, 2013 12:42 am 
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My apologise for the earlier post! It seems like I wasn't paddling as fast as I thought.

A thorough check on the distance revealed that I had paddled 2.5km in 20 minutes, not 4km as previously estimated. That puts it at a sustainable cruising speed of 7.5km/h (4 knots).

Many apologies for the gross over-estimation. I have edited the earlier post to reflect the new findings. Thanks for noticing and pointing out the seemingly impossible figure!


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PostPosted: Sat Feb 09, 2013 2:56 am 
lord high faltbotmeister

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No worries. Feeling (a bit) less wimpy now....:-)

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Pakboats Quest 135, Nautiraid Narak 460, 416 & K1 (sold my 550), First light 420, Feathercraft Wisper, Fujita Alpina AL-1 400, Incept k40 (for sale)
Non-folders: Cape Falcon F1. Beth sailing canoe, 2014 Hobie Adventure Island


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PostPosted: Sun Sep 10, 2017 1:43 pm 
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A very interesting discussion, but I did not read anywhere (did I miss it?) the theoretical upper limit of any displacement boat.

Perhaps competition kayak racers can get their boats into a planing mode (i.e. skimming over the surface) for very short distances, but for the rest of us ordinary paddlers, the absolute top speed, in knots, you can attain is given by the formula: 1.34 x square root of your waterline length in feet.

Which is probably why I can usually solo paddle my 17 Greenlander as fast as my friends' 15' speed machines. This is one time when size does matter.

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PostPosted: Thu Sep 14, 2017 11:39 pm 
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scotjack wrote:
A very interesting discussion, but I did not read anywhere (did I miss it?) the theoretical upper limit of any displacement boat.

Perhaps competition kayak racers can get their boats into a planing mode (i.e. skimming over the surface) for very short distances, but for the rest of us ordinary paddlers, the absolute top speed, in knots, you can attain is given by the formula: 1.34 x square root of your waterline length in feet.

Which is probably why I can usually solo paddle my 17 Greenlander as fast as my friends' 15' speed machines. This is one time when size does matter.

A year or two ago I read a great article (can't find it now :( ) discussing this. Generally, among kayaks of the same beam, longer kayaks have a higher top speed, but require more effort to maintain cruising speed (moderate effort) than a shorter kayak. The key is selecting the appropriate kayak size for the paddler's size and physical ability.

For smaller paddlers who aren't particularly strong a smaller kayak (14-16' long, 21-23" beam) is typically more appropriate because they'll be able to maintain decent cruising with only moderate effort. A larger, stronger paddler would be more well suited for a larger kayak (16-18', 22-24" beam) because they won't have difficulty maintaining cruising speed in such a yak the way most smaller paddlers will.


Last edited by Apathizer on Fri Sep 22, 2017 4:49 pm, edited 2 times in total.

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PostPosted: Fri Sep 15, 2017 7:08 am 
lord high faltbotmeister

Joined: Fri Oct 07, 2011 1:51 pm
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Location: Colombo, Sri Lanka
That's also my experience. It's to do with the lower wetted surface area of the shoter yak. By the way, I saw somewhere that kayaks can exceed the theoretical max speed for a displacement hull by a bit due to their high length to width ratio

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Pakboats Quest 135, Nautiraid Narak 460, 416 & K1 (sold my 550), First light 420, Feathercraft Wisper, Fujita Alpina AL-1 400, Incept k40 (for sale)
Non-folders: Cape Falcon F1. Beth sailing canoe, 2014 Hobie Adventure Island


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PostPosted: Fri Sep 15, 2017 7:11 pm 
knight of the folding kayak realm

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siravingmon wrote:
That's also my experience. It's to do with the lower wetted surface area of the shoter yak. By the way, I saw somewhere that kayaks can exceed the theoretical max speed for a displacement hull by a bit due to their high length to width ratio

Yeah, the lower wetted surface area of a shorter yak means less resistance, but it will veer sideways more with each stroke. Since kayaks are propelled from either side rather than the center of the hull they veer slightly to the opposite side with each stroke. This effect is glaringly obvious in short boats which track poorly. It's barely noticeable in long yaks (waterline ~16'<) which track strongly, but don't maneuver as well and are more difficult for small to average strength paddlers to propel due to the higher wetted surface area. Again, it's about intended usage and paddler size and strength.

It would probably take an especially strong and well conditioned paddler to exceed the theoretical max speed for anything other than quick bursts. I doubt anyone could maintain such effort beyond a short duration especially since it's usually unnecessary.


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