Weight and Efficiency

For flatwater canoeing, I have a question about boat weight and efficiency (roughly, speed). Consider two solo canoes, identical in all respects except for construction material. One canoe weighs 30 lbs, the other 40 lbs (the weights are notional and arbitrary). How will the two differ in performance, if at all, in (a) light winds and smooth water? (b) stiff winds and noticeable chop? Thanks in advance for your knowledgeable insights.

Weight and Efficiency
In my never to be humble opinion, the biggest gaine in efficiency will be durring the carry from roof rack to water and of course on the portage trail. Once in the water, the practical advantage of a 10# lighter boat is minimal. When you consider that the average paddler weights 150#-160#, add even a minimal amount of gear and the combined weight of paddler, boat and gear easily approaches or exceeds 200#. That 10# difference in hull weight is now 5% of the total package.



I’ve paddled identical flashfires, glass and kevlar side by side. On dead calm water the kevlar boat feels slightly more responsive but it is minimal.



I would consider the out of water advantages of the lighter boat to be more significant. The degree of significance increases in direct proportion to one’s age.



Marc Ornstein

Dogpaddle Canoe Works

Thanks

– Last Updated: Dec-29-07 5:06 PM EST –

Thanks Marc. Makes sense to me.

Edit -- Now I'll feel less guilt when I order that heavier, more durable canoe ... the one I REALLY want. :-)

Not much
I have been designing a kayak in software. It has drag figure that automatically calculate as you make changes. I have found that paddler weights make a difference. Like the difference in my 200 lbs and my Nieces 135 lbs in the same boat. But boat weight is barely even noticeable in the figures.



Take that for what it is worth of course.

Weight is weight – or not?
It seems like a 170 lb guy in a 30 lb canoe would be be confronted with the same physical demands as a 150 lb guy in a 50 lb canoe.



But maybe that’s only the case in what I call (above) situation (a) – light winds and smooth water. In less favorable conditions, maybe a difference in weight distribution leads to a different result. Maybe.



Before I retired, one thing I did was develop software application programs. For such programs (to a degree most users cannot appreciate), the results you get depend on the assumptions the developers and programmers build into the beast. Let the user beware!

About 2%
Probably about 2% with little or no loss in tracking. Could mean around 12 miles more over 10 days using the same energy.



Probably slightly and maybe not noticeable gains in responsiveness.



10 pounds is huge on portages. The difference between my 44 pound Wildfire and my 32 pound Magic on portages is very noticeable. My SO refuses to portage the heavy boat.

Sounds about right. Now, for some
purposes, the weight of the boat makes a bigger difference because one has to accelerate the boat with each stroke, and with each effort to turn it. Taking ten more pounds off a 50 pound whitewater open boat makes a big difference when fighting the thing through a slalom course.

I agree with that
My Novacraft Supernova is quite a bit more maneuverable than my Mohawk Oddysey 14, yet it seems like it takes more “OOOmph” to make a major correction with the Supernova. It certainly takes more power to get it moving. The Supernova weighs about 20 pounds more, and is about 10" longer, if I recall correctly.

Apples/oranges
Sorry if I sound argumentative GB, but the Odyssey and the Supernova are completely different hull shapes and dimensions. I think their differences would affect performance much more that their individual weights. The Odyssey is a general purpose canoe while the Supernova is a specialty semi-ww tripper. Yes, they also have different weights but I doubt if that has very much to do with their differences in performance. I think it’s more realistic to compare the same model boat in varying lay-up weights.



The poster’s question was whether or not a few pounds make any difference in the performance of a flatwater canoe. I have paddled various canoe models over the years in varying (weight) layups in flatwater situations. While the weight makes a major difference on the portage trail on the water a few pounds difference makes no appreciable/noticeable difference in performance in my humble opinion. Marc nailed it with his answer. My 2 centz - RK

My 2 cents about the Odyssey.
The Mohawk Odyssey 14 is a capable river tripper (which includes whitewater), the Solo 14 is their GP boat. The Odyssey just happens to be reasonable on flatwater as well. Having never paddled a SuperNova, it’s my understanding that it’s somewhat dryer/more capable in the big stuff, but not as fast as an Odyssey.



Phreon

weight
I think you should buy the stronger boat and never worry for a second about giving up performance. I’m told that stiffer hulls are more efficient for energy transfer so you may even get a small advantage that offsets the small increase in mass. Since it’s easy to feel the most subtle differences between boats I can believe that a super light boat might feel slightly more responsive since there is a bit less inertia resisting turning but there would be no practical difference.


Bonus Gear
As noted before, on the water the weight difference will make very little difference, on the portage it will be a big difference. Taking 10# off the boat weight lets you add 10# of gear weight and still have the same total weight to tote across the portage. It can make the difference between a single trip across the portage, or two trips. And two trips means walking 3X the portage length.

Bill

My two cents (2 1/2?)

– Last Updated: Dec-31-07 12:52 PM EST –

The Odyssey may be a capable river canoe – not just a general purpose boat. I did not mean to slam that canoe... "General purpose" was my just my impression by comparison to a Supernova - having personally spent a bunch of time in a Supernova. The Odyssey is not nearly as rockered as the Supernova. It also has a much flatter bottom (in cross section) compared to a Super which is very oval. Different lengths/widths as well. One can spin a Supernova without much effort without even heeling – can’t say that about an Odyssey. Heel a Super and TRY to quit spinning! Ha! A Super is an incredibly maneuverable canoe – in fact anyone I’ve ever met who paddled one has said (in effect) the trick is getting it to go straight. With it’s wide rounded belly getting it up to speed is some work. It’s a very different canoe in real world paddling compared to an Odyssey. In my opinion there are clearly enough differences to say it’s an apples/oranges comparison – which was my point. The original posters question had to do with whether or not weight makes a difference in flatwater paddling. The answer can only be ascertained when comparing the SAME hull design, length, width, etc. It’s not a valid comparison in my opinion when there are other factors (like those many differences stated above) to consider. RK

I have no problem with that

– Last Updated: Dec-31-07 1:30 PM EST –

By commenting on the effort required for abrupt maneuvers, I was dealing with the subject of accelerating that extra mass, which was the same subject addressed by g2d. On a similar note, I don't particularly care for the sticky stern of the Bell Yellowstone, but its lighter weight really made it "feel" a lot more lively than the Supernova, even though it really doesn't maneuver as well (talking about sudden acceleration in the form of abrupt maneuvers again).

For basic cruising, you have a good point that the two boats are just too different to be compared in that way. I just thought g2d was on to something with situations where velocity changes are the norm. That's why I put my comments after his, rather than in the main stream of the thread. Good of you to bring this up and keep things clear, though.

two collateral effects
I agree that weight per se probably doesn’t make a lot of difference, but with a lighter boat you often get two more things: more stiffness and finer lines (the latter mainly when you’re getting lighter by going from plastic to composite). Those changes can make a noticeable difference in handling.



– Mark

Yes my friend
I agree completely. Always good discussing things with you GB – always the gentleman.



BTW, I share your dislike of the Yellowstone Solo’s sticky stern. I paddle one often – in fact after all these many years and now with a few different solos to choose from it’s still my most often used small river runner… (probably having to do with the Royalex as much as anything I suppose, for me anyway). It’s a great “kick around” canoe. But that dern sticky stern… argh! As I’ve said so many times differential rocker is just a PIA as far as I’m concerned – it’s like training wheels – which is okay I guess – until you’ve outgrown the need… or just want to play more… DF is really for those who haven’t learned to paddle straight – but here I go again… off topic. I’ll shut up now! ;^) Have a Happy New Year! RK

getting back to the original question
I’m sure the answer is clear mathematically but I don’t know what it is.



It seems logical that a difference would exist. Would it be noticable, not sure? Would be interesting to know the actual measured difference.

Efficiency of some designs may differ and result in larger or smaller difference among hulls.



If you pull a sled as you ‘pull’ a canoe, the heavier sled would be harder to pull. “Harder” being a relative term. Some books describe paddling as if you were pulling the canoe to the planted paddle.



Psychologically you would gain an edge and that is a big part of the battle.



The heavier the boat, the less use it gets. Again, heavy being relative to the user’s physical condition and psyche.

great subject
i race J boats and mine is about 15 pounds heavier than the lightest carbon boats on the market. that’s A LOT for a racing boat, considering mine weighs 37 pounds. it may not make a huge difference when rec. paddling, camping or fishing, but 15 pounds is a lot of weight when you’re racing for 2.5 hours or so.



there must be a difference while paddling, otherwise people would only buy carbon for the portages.

Heavy boats simply spend more time
in the garage. Have seen it time and time again. If its not comfortable to lift it doesn’t go out as much.



Two identical hulls that differ by a few lbs may have the lighter one more affected by wind and have a different hull shape in the water as not as much water is displaced.



Most paddlers cannot tell a ten percent difference so I figure its not worth worrying about.



The sticky Yellowstone stern was an intentional design parameter to help people who have not developed their paddling skills go straight.



However a boat in carbon and one in Royalex even if they are the same hull are rarely the same shape. The latter will tend to be blunter bowed.



If you are a racer of course every ounce counts and you probably have had your hull analyzed for various efficiencies at different weights with a CAD program.

Most helpful (I think?)
Many of these posts have opened my eyes to things I like to know about. Thanks to everyone who has contributed.