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PostPosted: Tue Jul 17, 2012 1:25 pm 
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It's always bothered me that the Adventure kayak is so fast and easy to pedal, but it becomes much slower to pedal when in AI mode with the sail furled. This would be partly due to the extra weight and windage of the akas, amas and mast, but I think the bulk of the problem is due to the amas dragging in the water.
A simple solution would be to get the akas bent a little, so as to raise the amas, say, 3".
It would cause the boat to heel a bit more, but I usually hike out to keep the amas level anyway. The amas on the TI seem to sit right out of the water when it is running flat and it heels over further than the AI with no apparent deleterious effect.
Anyone think this is a dumb idea? Am I missing something?

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PostPosted: Tue Jul 17, 2012 2:02 pm 
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My two original AI's were different in the aka angle. One's ama were much higher than the other. I never noticed much difference in pedaling or handling between boats.

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PostPosted: Tue Jul 17, 2012 3:12 pm 
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Honestly, I'd like to see the AI hull revamped - split it right along the mold line and add 1 inch there, put it back together, and you'd have a much drier seat and tankwell, plus the Amas would ride a little higher before touching the water.

Now having said that, I haven't found the Amas to really impede the speed of the AI in pedal mode by very much. The boat still feels pretty fast to me considering its size and weight.

If you do decide to bend the Akas a little, make sure to have it done by somebody with equipment that can make such a bend without crimping the tubes. It would only take a very slight amount at the junction area to the boat, to raise the Amas a noticeable difference.

Have you considered checking to see if the TI Akas are set to a different, higher angle? If so, maybe you could obtain a set of those and dispense with bending anything.


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PostPosted: Tue Jul 17, 2012 3:25 pm 
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Well I know the AI pedals much faster in Adventure mode. I guess I should be scientific and take the AI out with the akas fitted upside down and braced by ropes and see if it pedals faster. I'm guessing it would be much cheaper to get the local metal shop to bend the akas than to purchase a set of TI akas.

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PostPosted: Fri Jul 20, 2012 8:14 pm 
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How about adding some spacers made from cutting board between the cross bars and deck and reattatch with longer bolts. I guess also raiseing the sail by x amount won't hurt any thing. Don't know, never tried it. A flange from same cutting board for the mast reciver could be made to match spacers. :wink:


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PostPosted: Sat Jul 21, 2012 3:11 am 
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Careful, if you have the newer TI style akas, they are not symmetrical. There tube walls are thinner on the sides and MUCH thicker on the top and bottom.

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PostPosted: Sat Jul 21, 2012 7:34 pm 
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Chris, I meant to get back to you on this but got distracted.

First off, yes, it's a loopy idea! ;-). But if you have to try it, I would avoid cold bending the tubes. They are more fragile than you think and can developed stress cracks under the paint. If you went with heat bending you'll just muff the paint job. Plus you'll have to do 2 bends on each Aka and they all need to be calibrated.

Better to cut a few inches off the tube ends and then rivet on a new collar and end plug. You can raise the Amas cheaply and accurately this way and even add a little lift to the Ama nose if you want, to further reduce resistance.

Frankly though, I think the AI benefits from having MORE Ama, not less. Putting TI floats on an AI really improves the ride.


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PostPosted: Sun Jul 22, 2012 2:02 am 
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Thanks for the thoughts guys. Really, before I make any radical alterations, I need to test it by taking the boat out with the amas and akas on upside down and the mast set, so that the only variable will be the amas not dragging in the water.
I can understand why the idea might have little relevance in Hawaii, where you are in the sea virtually all the time, usually with good winds.
Where it would be useful to me is, there are a number of situations where I need to travel (pedal) down a creek for several kilometres before reaching open water. Also, it's not unusual for the wind to die completely in our estuaries. The Adventure is very fast in kayak mode, so I'd like to be able to approach that performance with the amas deployed. Also, when sailing, I feel that the performance has already been improved in light winds by using the Quarterdeck to keep the amas always level and I am hoping it will improve even more if the amas can be kept completely clear of the water.
As it happens, I have an old set of crossbars and akas which look terrible, but still seem to be structurally sound, so I can experiment with them.
I'll report back when I've had a chance to do my upside down ama experiment.

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PostPosted: Tue Aug 28, 2012 6:02 am 
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OK, I did it. I got a metal shop to bend my old akas, so as to raise the amas about 6".

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I took it out for a test sail today, using the Quarterdeck. Surprisingly, I didn't notice a big improvement in pedalling, but I was pedalling from the Quarterdeck, which, though adequate, is less efficient than pedalling from the conventional seat.
Where I did notice a big difference was in sailing in light winds, with the drive pulled. It took a bit of getting used to, keeping the boat balanced and level, but the improvement in performance was striking. I could only estimate the wind strength, but from my experience, I would swear it was no more than about 5 knots and the boat was doing 5 knots on a broad reach and 4 knots close hauled (GPS readings). Given the AI is generally reckoned to do no more than half the wind speed, that's a big lift. Even when the wind died almost completely, the boat kept moving.
I got the odd gust up to about 10 knots and the difference was not as noticeable. I think this was because I was not able to keep the leeward ama completely out of the water.
Overall, it seems to have been a very worthwhile mod, but I am still getting the hang of sailing this way. It feels a bit like riding a surfboard.

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PostPosted: Tue Aug 28, 2012 10:22 am 
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She's even more unique (for now) with your quarterdeck and now the higher ama/aka. Pretty soon everyone will be doing it. :)

I await further reports. The ama look more like Hawaiian outrigger canoe ama now.

Good sailing...

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PostPosted: Tue Aug 28, 2012 11:14 am 
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interesting read, I like the position of the new seat

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PostPosted: Tue Aug 28, 2012 12:57 pm 
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Cool. Hope to see some video when you get into real wind.

I notice you did not also correct the angle of the dangle for the Amas. The keels are offset now. When the sailing gets more intense and these do begin to bury, it will be interesting to see if they try to turn the boat.

As I recall, you really wanted to do this for longer pedal treks. Too bad it didn't provide the glide you wanted there.

Best way to test things would be to have one or more stock AIs track you in average winds/flat water and all of you sail/pedal from the cockpit.


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PostPosted: Tue Aug 28, 2012 3:09 pm 
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NOHUHU wrote:
I notice you did not also correct the angle of the dangle for the Amas. The keels are offset now. When the sailing gets more intense and these do begin to bury, it will be interesting to see if they try to turn the boat.

I thought about that NOHUHU, but it seems to me that by the time the ama is in the water, the hull will be heeled over further, but the angle of the ama to the water will be pretty much the same. The extra heel of the boat is sure to have some effect on the steering, but I know that in winds of over 20 knots, I can keep the the ama from burying by hiking out, without having to furl the sail. Time will tell..........

NOHUHU wrote:
As I recall, you really wanted to do this for longer pedal treks. Too bad it didn't provide the glide you wanted there.

Best way to test things would be to have one or more stock AIs track you in average winds/flat water and all of you sail/pedal from the cockpit.

Yeah, unfortunately, I didn't have time to test the boat from the cockpit. I built the quarterdeck to match the newer akas/crossbars. Normally I can just turn it around, if I want to sit in the cockpit. It doesn't fit the older crossbars so well, so I had to strap it down and I was having too much fun sailing to fiddle with it. If I decide to stick with this aka setup, I'll knock out a new quarterdeck to fit.
Coincidentally, Stringy came riding past the boat ramp on his bike as I was packing up, so we've agreed to get together sometime to compare the AI's in both modes.
I've got to say, I can't see this providing much of an advantage while sailing from the cockpit. I needed to be able to shift my weight around while sitting on the quarterdeck, to keep the boat flat.

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PostPosted: Tue Aug 28, 2012 4:02 pm 
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Chris, I totally missed the fact that you were swapping new TI style bars for the "altered" AI originals. And that your 1/4 deck would not fit.

With that in mind, did you compare the Ama heights of the old vs new stock setups? Seems there is more rake on the new bars, but have not seen anyone measure the these angles. In other words, are the Amas a little higher to begin with on the new bars?

With my original "pinned" bars, when sailing balanced from the Hakas in >12 knots of wind, there is very little drag from the Amas. So I am thinking this already maximizes the displacement mode of the hull. In other words, it's very close to sailing without Amas, although they still provide welcome stability in swell conditions and aid in turning.

I hope we get to see you take the 1/4 deck out sailing- WITH NO AKAs/AMAs. That would be a HOOT, and tell you what you really want to know. Godspeed! :wink:

And actually, you could easily test this by leaving the leeward Akas off and flying the windward set for awhile. (Roll video!)


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PostPosted: Tue Aug 28, 2012 4:20 pm 
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NOHUHU wrote:
Chris, I totally missed the fact that you were swapping new TI style bars for the "altered" AI originals. And that your 1/4 deck would not fit.

With that in mind, did you compare the Ama heights of the old vs new stock setups? Seems there is more rake on the new bars, but have not seen anyone measure the these angles. In other words, are the Amas a little higher to begin with on the new bars?

With my original "pinned" bars, when sailing balanced from the Hakas in >12 knots of wind, there is very little drag from the Amas. So I am thinking this already maximizes the displacement mode of the hull. In other words, it's very close to sailing without Amas, although they still provide welcome stability in swell conditions and aid in turning.

I hope we get to see you take the 1/4 deck out sailing- WITH NO AKAs/AMAs. That would be a HOOT, and tell you what you really want to know. Godspeed! :wink:

And actually, you could easily test this by leaving the leeward Akas off and flying the windward set for awhile. (Roll video!)

With the new style akas, the amas still drag in the water a bit when the boat is flat.
I think the advantage of the raised amas disappears in higher wind anyway.
I am planning to sail the boat from the quarterdeck with no amas, but I was waiting for summer - for the water to warm up a bit :roll: :roll: :roll:

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