Surf ski speeds

For some strange reason, when I posted a link to Van Dusen Racing Boats/ Composite Engineering, I got a message back that said my post was considered spam! At any rate, go to www.composite-eng.com and you'll find the info on the Mohican and purchasing one. The Mohican is one of the top flat water racing boats, noted for excellent shallow water speed (but don't try to use it in big conditions like a ski).

@aurelius
reg. your cycling compariosn, e.g. google: barton 10k surfski speed comparison

for me for example ... on flat water, for fitness paddling, as an "if at all" intermediate paddler, my not so busy schedule would allow for those extra 30s compared to the next faster model though ....

Sometimes, it's not about getting there 20 seconds earlier on a given surfski, or even 3 minutes earlier. The incredible feeling of the challenge and great glide ratio speaks to me.

I have paddled with the same group 4 plus days a week, in all sorts of conditions, in all sorts of boats, in various stages of fitness for the last 10 years. I reckon the only way to tell how fast a boat is in real life conditions is to see whether your mate in his new v12 or uno max or carbon sei or elite s or whatever, is further in front or further behind than usual. If he's further in front, for some funny reason over the next couple of months everyone else seems to own the same ski.

Winter and summer tend to bring out the best in different boats.
Some boats surprise you, most never live up to the hype.

If you only paddle in flat water with no bumps and you're a legend, buy something long and skinny with no rocker. (or any nelo ever made apparently). If there are bumps and you're not a legend buy something else.

If you're big boned with a large backside buy a zeplin. Never mind that it doubles the weight of your car when you put one on the roof. I've never owned one or paddled one. But blokes that would be in a different postcode at the rear in sr's and sei's and ions and se's etc seem to be in front of me. It's costing me money trying to keep up.

The only way to compare boats is to paddle with someone you know and compare results.

Uffilation wrote: google: barton 10k surfski speed comparison

on flat water, for fitness paddling, as an "if at all" intermediate paddler,
My not so busy schedule allows for those extra 30s compared to the next faster model though ....

Looking at those results over a 10KM distance, it appears that the differences between the fastest skis are pretty minimal. Certainly too small to matter to a recreational kayaker like myself. There's a sizeable ~0.5 mph difference between my Epic V7 and Stellar SR, and I'd be willing to bet the difference would be even greater once I get my paddling technique down. When I hit 7.5 mph in the SR, I start flailing around and have difficulty maintaining a straight line. It feels as if I have the muscle power to go even faster, but I doubt I'd be able to keep the boat upright if I attempted it.

red_pepper wrote: For some strange reason, when I posted a link to Van Dusen Racing Boats/ Composite Engineering, I got a message back that said my post was considered spam! At any rate, go to www.composite-eng.com and you'll find the info on the Mohican and purchasing one. The Mohican is one of the top flat water racing boats, noted for excellent shallow water speed (but don't try to use it in big conditions like a ski).

That Mohican is certainly tempting, but I wouldn't be able to do it justice at my present level of skill and physical condition. Since I don't race nor ever aspire to race, buying one of these boats probably makes no sense at all, but a narrow focus speed weapon like this is still very appealing to me on a conceptual level.

Hi Red Pepper,

For some strange reason, when I posted a link to Van Dusen Racing Boats/ Composite Engineering, I got a message back that said my post was considered spam!

Sorry about that - I have to be REALLY careful about spam, so I'd rather the system erred on the side of caution.

Here's the link to the Facebook page.

Van Dusen Facebook page

The URL listed on this page redirects to the link you already gave:

www.composite-eng.com/

@aurelius,
which is why I posted it that way. While I understand the excitement of a boat that accelerates fast and is super reponsive and has great glide ... I still wanted to counterbalance a bit, because one often reads that a ski is "unbelieveably fast" etc. ... but the first Q is, what will you use your ski for ... and it seems that many non-racing, non ocean paddling, single fitness paddlers get easily caught by longer/thinner = faster instead of stability before ability and dedicated technique training and seem to want the next "supposedly so much faster" boat too early. E.g. as long as one paddles the V7 on a 10+km course way below the avg. speed given in that list = no need to switch to the V1Xes for those supposed extra km/h.

robin.mousley wrote: Hi Red Pepper,
...
Sorry about that - I have to be REALLY careful about spam, so I'd rather the system erred on the side of caution.

...

Thanks, Rob. I can appreciate that! You do have a rather robust spam detection system; I tried to reply with a thanks, quoting your whole message, and it got kicked back as spam again.

Steve

Aurelius wrote: Just for clarification, I recently tested two skis made by Stellar on a smooth lake in pretty much windless conditions. One was the SR and the other was the SEI. The SEI was not only rated the faster of the two, but the one I happened to test was the lightweight Excel layup, weighing just 26 lbs compared to the SR's Advantage layup at 33.1 lbs (according to their website).

Yet despite these differences, my top speeds in both boats were identical according to my GPS. The SEI was noticeably less stable than the SR at the start, but any instability issues went away once I reached speeds of 5+ mph. I repeated the test several times, but in each case the result was the same: no speed advantage at all for the SEI. Given the superior stability of the SR and it's much more attractive price, that's the one I ended up buying. I don't regret my decision in the least, but I am very puzzled as to why the SEI's more aggressive hull geometry and lighter weight didn't translate into better speed. My only thought is that perhaps whatever speed advantage it does have is so minuscule that it simply didn't register during the relatively short sprints I performed on the lake, but that it might show up in a race several hours long. Or could it be that the SEI's performance advantage only shows up in turbulent ocean water?

I haven't found the speed differences between ski layups to be all that significant. Acceleration tends to be more noticeable, as does stability, and in this case the extra stability of the Advantage layup SR very possibly enabled you to perform better in the SR.

Another possibility may lie in the ergonomics of the boats - how well you fit the respective cockpits (the newly redesigned SR gen 2 cockpit may place you in a better paddling position), and how your weight was distributed. If you were testing a 2nd gen SR, the cockpit has been moved forward and the hull has been redesigned for additional performance. It may be that your positioning in the SEI distributed your weight a little more towards the stern, resulting in an out-of-trim condition that slowed your speed. Just recently a gal in our local racing group was having trouble getting the speed she expected out of her S18S (she is quite short). With her short legs more of her weight was in the cockpit seat without much leg weight forward of the seat. By sitting on some foam closer to the hump and moving her whole body forward (about 6"), the trim on the boat was optimized and she says she picked up 0.5 mph!

A third possibility for the discrepancy is the speed you were able to attain; a longer waterline/narrower beam tends to become more advantageous at higher speeds. At lower speeds, the shorter waterline (less surface drag) may offset the longer, narrower boat's reduced shape drag.

Just some thoughts on your conundrum.

Just to add a little more re layups...

Years ago there was a company called Red7 that manufactured skis here in SA. At one point we got our hands on two boats that were identical in everything but layup.

We had a light cork/glass composite boat (lovely build, had clear areas in the cladding where you could see the cork sandwich) and a "heavy" carbon boat.

They both weighed about 12.6kg, but the carbon boat was much stiffer.

My buddy Dale and I paddled both boats in choppy water and concluded that we found carbon version significantly more tippy than the cork version.

Here's the article on the test: Stiffness and Stability

upper interesting to see two tests done on two skis weighing the same... but having different flex.

I don't like a ski to feel like a noodle either... but a ski that's too stiff isn't the best for my old age. After about 20k, I feel an additional strain on my body.

Absolute rigid skis feel like THIS:
(single speed, rigid frame, no suspension)

A little bit of "give" feels more like THIS:
(plenty of gears, plenty of front and rear suspensions)

It's fun, but I may be too old for the super rigid stuff.

red_pepper wrote: I haven't found the speed differences between ski layups to be all that significant. Acceleration tends to be more noticeable, as does stability, and in this case the extra stability of the Advantage layup SR very possibly enabled you to perform better in the SR.

Another possibility may lie in the ergonomics of the boats - how well you fit the respective cockpits (the newly redesigned SR gen 2 cockpit may place you in a better paddling position), and how your weight was distributed. If you were testing a 2nd gen SR, the cockpit has been moved forward and the hull has been redesigned for additional performance. It may be that your positioning in the SEI distributed your weight a little more towards the stern, resulting in an out-of-trim condition that slowed your speed. Just recently a gal in our local racing group was having trouble getting the speed she expected out of her S18S (she is quite short). With her short legs more of her weight was in the cockpit seat without much leg weight forward of the seat. By sitting on some foam closer to the hump and moving her whole body forward (about 6"), the trim on the boat was optimized and she says she picked up 0.5 mph!

A third possibility for the discrepancy is the speed you were able to attain; a longer waterline/narrower beam tends to become more advantageous at higher speeds. At lower speeds, the shorter waterline (less surface drag) may offset the longer, narrower boat's reduced shape drag.

Just some thoughts on your conundrum.

Very interesting. I didn't realize that weight distribution was such a big factor in hull speed. It probably wouldn't apply to me, however, since I have a pretty average build (6'-0" tall, 32" inseam, 178 lbs).

I'm inclined to think that what may account for my results is the fact that all the expert paddlers who test surf skis and publish their results are operating in a completely different environment. On a smooth lake, the only thing I need to worry about when it comes to speed is strength and technique. But on the ocean, you have to time your strokes properly to coincide with the motion of the waves, and you're using waves to accelerate. Perhaps in those conditions the longer, narrower SEI would have an advantage over the SR. Whatever the case may be, I intend to give the SEI and perhaps even the SEL another shot in a year or so, once I've gotten completely comfortable on the SR.

for flat water water line
let someone make a pic of you sitting in it, see where the front is reg. waterline,
then clmap a sock filled with 0.5-1kg sand under the front handle (attach with tape) or in front of the foot plate or for those that have it, in the front hatch ... compare the pics and waterline and paddling feel/speed ... for the fun of it

Uffilation wrote: for flat water water line
let someone make a pic of you sitting in it, see where the front is reg. waterline,
then clmap a sock filled with 0.5-1kg sand under the front handle (attach with tape) or in front of the foot plate or for those that have it, in the front hatch ... compare the pics and waterline and paddling feel/speed ... for the fun of it

I may have an even better option. The Stellar dealer I bought the SR from tells me he knows an expert paddler in my area of my size and weight and who also happens to own a second generation SR. Hopefully we can arrange a meeting to see what he has to say.

robin.mousley wrote: Just to add a little more re layups...

Years ago there was a company called Red7 that manufactured skis here in SA. At one point we got our hands on two boats that were identical in everything but layup.

We had a light cork/glass composite boat (lovely build, had clear areas in the cladding where you could see the cork sandwich) and a "heavy" carbon boat.

They both weighed about 12.6kg, but the carbon boat was much stiffer.

My buddy Dale and I paddled both boats in choppy water and concluded that we found carbon version significantly more tippy than the cork version.

Here's the article on the test: Stiffness and Stability

Rob - was there any difference in how the boats were constructed? I've found that while a heavier layup is generally more stable (when the weight is distributed throughout the structure), some heavier boats (like the Stellar Multi-Sport construction) feel similar to the lighter layups in reactivity. In the case of the Multi sports, the hull is a carbon-Kevlar weave without a core, so it's relatively light, but there's a heavier keel running down the center of the boat. This allows the boat to be reasonably stiff when paddled, but able to absorb a lot of punishment if something is hit. But it also concentrates the mass closer to the centerline of the boat, and hence the more lively feel (reduced mass moment of inertia).

I also came to paddling from a club cycling background as have a lot of my paddling buddies. We’ve come to the conclusion that comparing equipment for the two sports is a real trap because provided you can adjust the bike to fit there is very little about it that influences your ability execute good pedalling technique to maximise your power transfer.

In surfski paddling your ability to execute a good forward stroke regardless of the sea conditions trumps nearly everything else when it comes to speed and as others have suggested this is influenced by a multitude of factors including boat design and layup vs your leg length vs your weight vs your power. Speed comparisons in quantitative terms provide some info but “Your mileage will vary and will contain traces of nuts” for each craft in each layup with your level of ability.

Sometimes though, we have to simplify things a bit, because the answer may be right in front of us.

You want to go faster?
Try different skis.

When you try a ski that allows you to go faster than your buddies, keep paddling it to see if you are still faster in ALL CONDITIONS. If everything holds true, you have got yourself a good match for your abilities.

First, I don't mean this to sound harsh but it sounds like you need more time in ski's.
Faster ski's are about potential and not a given. If you are not 100% in the SR you surly won't be in the SEI. It's hard to get any sence of real speed difference between ski's unless you can do them justice. That means good wing technique, fitness and solid stability in the ski. Lots of people come from sea kayaks to surfskis and are disappointed in the lack of the speed increase they were expecting, It's not the ski's fault. The same goes for trying out a faster ski. I have a Sellar SEL and am not really worthy. It IS a lot faster than my v10 sport but in a long race it's not that much faster for me. Why? Because im not strong enough to drive the boat that hard. I can sprint or paddle a mile a lot faster than the Sport but that's where my strangth and fitness end and where my 7 mph 10k begins. So basically, if you can't drive the SR with good technique and solid stability then the SEI will never feel much faster than the SR if at all.

Bill

Newbflat wrote: First, I don't mean this to sound harsh but it sounds like you need more time in ski's.
Faster ski's are about potential and not a given. If you are not 100% in the SR you surly won't be in the SEI. It's hard to get any sence of real speed difference between ski's unless you can do them justice. That means good wing technique, fitness and solid stability in the ski. Lots of people come from sea kayaks to surfskis and are disappointed in the lack of the speed increase they were expecting, It's not the ski's fault. The same goes for trying out a faster ski. I have a Sellar SEL and am not really worthy. It IS a lot faster than my v10 sport but in a long race it's not that much faster for me. Why? Because im not strong enough to drive the boat that hard. I can sprint or paddle a mile a lot faster than the Sport but that's where my strangth and fitness end and where my 7 mph 10k begins. So basically, if you can't drive the SR with good technique and solid stability then the SEI will never feel much faster than the SR if at all.

Bill

No doubt I could benefit from more time in a surf ski. So with that in mind, I contacted Wesley Echols. Unlike me, Echols is a veteran surf ski racer. Having tested both the Stellar SR and SEI, I was curious as to why he rates the SEI as being "significantly faster" than the SR. His response was as follows:

"The SR 2G is a wonderful all around ski in flat or ocean with excellent glide and handling. The SEI is significantly faster than SR in comparable rudders, and layup in all conditions flat or ocean, not by much but it is. I most recently did a .25 mile time trial with SR excel, SEI excel, and EVo2 carbon back to back and this was on top of all my other data over the years. The SEI still was a few seconds faster."

So it turns out that what Echols considers "significantly faster" amounts to only a few seconds over the distance of a quarter mile. A microscopic variation like that is not something my GPS is capable of detecting. Even if it had, it could easily have been accounted for by other variables like changes in fatigue level between test runs and changes in wind direction and/or force.