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dtm said..

frenchfoiler said..

PeterP said..

frenchfoiler said..
Kujira 1440 is also good for DW, for me I would borrow my friend's 1440 when it is light wind.

WakeThief seems to indicate getting lift-off is not one of the 1440's strong points - what is your take on that?

I think the 1440 is a good dw light wind (for my size and my dw experience). On small bumps it has a really good glide, really effortless, the speed range is really interesting as it goes from really low to high.
I did a dw run without much enregy (no swell no big bumps) and the last 2km were side wind, I was able to glide side ways super easy, which I wouldn't have done with another foil I've tried (I tried right away the same run with my Sig 250 and it wasn't good).

Interesting take I would have thought the Sig 250 beast would have out pumped it all day with a lot more glide? I like the 1440 agree it's a good wing and pumping plus glide is impressive though I find it tracks sometimes through the water I was thinking the tips are going the wrong way and should be cut off to loose up, what are your thoughts on this?

I guess that bigger foil feels too slow now even on a light wind dw. It is just like on wave, I don't use anymore a bigger foil even on tiny waves, I still ride my smallest foil. Dw is different has you need to stay up all the time but still you don't want someting too slow where you are used to faster foil.

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frenchfoiler said..

dtm said..

frenchfoiler said..

PeterP said..

frenchfoiler said..
Kujira 1440 is also good for DW, for me I would borrow my friend's 1440 when it is light wind.

WakeThief seems to indicate getting lift-off is not one of the 1440's strong points - what is your take on that?

I think the 1440 is a good dw light wind (for my size and my dw experience). On small bumps it has a really good glide, really effortless, the speed range is really interesting as it goes from really low to high.
I did a dw run without much enregy (no swell no big bumps) and the last 2km were side wind, I was able to glide side ways super easy, which I wouldn't have done with another foil I've tried (I tried right away the same run with my Sig 250 and it wasn't good).

Interesting take I would have thought the Sig 250 beast would have out pumped it all day with a lot more glide? I like the 1440 agree it's a good wing and pumping plus glide is impressive though I find it tracks sometimes through the water I was thinking the tips are going the wrong way and should be cut off to loose up, what are your thoughts on this?

I guess that bigger foil feels too slow now even on a light wind dw. It is just like on wave, I don't use anymore a bigger foil even on tiny waves, I still ride my smallest foil. Dw is different has you need to stay up all the time but still you don't want someting too slow where you are used to faster foil.

Yeah understand I've only used the 1440 down wind on prone it's a google wing I just find it could be loser turning it
but the pumping and glide is great

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frenchfoiler said..

dtm said..

frenchfoiler said..

PeterP said..

frenchfoiler said..
Kujira 1440 is also good for DW, for me I would borrow my friend's 1440 when it is light wind.

WakeThief seems to indicate getting lift-off is not one of the 1440's strong points - what is your take on that?

I think the 1440 is a good dw light wind (for my size and my dw experience). On small bumps it has a really good glide, really effortless, the speed range is really interesting as it goes from really low to high.
I did a dw run without much enregy (no swell no big bumps) and the last 2km were side wind, I was able to glide side ways super easy, which I wouldn't have done with another foil I've tried (I tried right away the same run with my Sig 250 and it wasn't good).

Interesting take I would have thought the Sig 250 beast would have out pumped it all day with a lot more glide? I like the 1440 agree it's a good wing and pumping plus glide is impressive though I find it tracks sometimes through the water I was thinking the tips are going the wrong way and should be cut off to loose up, what are your thoughts on this?

I guess that bigger foil feels too slow now even on a light wind dw. It is just like on wave, I don't use anymore a bigger foil even on tiny waves, I still ride my smallest foil. Dw is different has you need to stay up all the time but still you don't want someting too slow where you are used to faster foil.

A lot of posts on this since I last looked. I see a few of my videos have been posted - I'm the geezer ladder jumping etc.
I agree with Frenchfoilers post about using smaller and smaller foils wholeheartedly, once you get used to smaller foils you learn to utilise their efficiency so using them in smaller and smaller conditions becomes possible. Where I was using the Axis 1300 & 1150 for dock starting I'm now preferring the Kujira 1440, and for pretty much everything else, where I was using the kujira 1210 I'm now using the 980.
Piros has it spot on when he said that the same foil will feel different to other people because of your style and the conditions you're riding in, as well as if it's DW, tow, prone etc, including what tail you use - it all makes a big difference.
There's a few posts here that made me wonder what the hell was going on, like Eppo's post about the kijira being as slow as balls - I'm glad it got cleared up later that he was referring to the 1440, would have been nice to have known that at the start - of course a foil of 1440cm2 will be slower compared to a foil of 980cm2. I think it's well known now that the kujiras aren't the fastest foils out there within their size/performance range (having said that they certainly can't be considered slow by any means) but IMO that's part of the kujira's strength - they seem to be able to match the speed of the waves or swell rather than outrun it which means you can focus on turning when you want to, rather than having to adjust your turns to control your speed or your position on the wave to prevent yourself from outrunning the wave. I also think that the kujira's have been designed primarily as a surf foil and as such they need to be treated in this way if you're going to get the best out of them. Yes they are awesome for downwinding and winging as well, and again IMO this makes them one of the most versatile foils out there - their range of use is just phenomenal, but if speed is your priority in a foils performance characteristics is speed then you'll have to go away from the kujiras - but then you'll be missing out on all the rest they offer that most foils can't match - that lovely surfy feel, drive through turns, ease of pumping at high and low speed, low end as well as high end performance etc etc. I've used the ART 999 a lot as well and although I love it for it's speed, glide, efficiency and pumping, for me the 999 is primarily a DW foil that also surfs and wings very well, whereas the kujiras are surf orientated foils that also downwind and wings very well.
Although I haven't used the Lift HA 120, from what I've heard it beats the kujira 980 in terms of top end performance. From what i've heard it's faster, it turns equally as well (possibly better) it pumps like a beast - BUT it's stall speed is higher so needs to be kept faster to utilise its pump performance, and it's not so forgiving of mistakes. The way I heard it summed up that made most sense to me was that the 120 is best suited to those who want top end performance all the time, whereas the 980 is for those who want a foil that can handle top, mid and bottom range well, and while it may not be master of any, it's damn near close enough! The 1210 and 1440 are equally as good in terms of having such a massive performance range, just on an increasing scale of size. At the end of the day it's down to what your style needs from a foil.

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Dommo49 said..

frenchfoiler said..

dtm said..

frenchfoiler said..

PeterP said..

frenchfoiler said..
Kujira 1440 is also good for DW, for me I would borrow my friend's 1440 when it is light wind.

WakeThief seems to indicate getting lift-off is not one of the 1440's strong points - what is your take on that?

I think the 1440 is a good dw light wind (for my size and my dw experience). On small bumps it has a really good glide, really effortless, the speed range is really interesting as it goes from really low to high.
I did a dw run without much enregy (no swell no big bumps) and the last 2km were side wind, I was able to glide side ways super easy, which I wouldn't have done with another foil I've tried (I tried right away the same run with my Sig 250 and it wasn't good).

Interesting take I would have thought the Sig 250 beast would have out pumped it all day with a lot more glide? I like the 1440 agree it's a good wing and pumping plus glide is impressive though I find it tracks sometimes through the water I was thinking the tips are going the wrong way and should be cut off to loose up, what are your thoughts on this?

I guess that bigger foil feels too slow now even on a light wind dw. It is just like on wave, I don't use anymore a bigger foil even on tiny waves, I still ride my smallest foil. Dw is different has you need to stay up all the time but still you don't want someting too slow where you are used to faster foil.

A lot of posts on this since I last looked. I see a few of my videos have been posted - I'm the geezer ladder jumping etc.
I agree with Frenchfoilers post about using smaller and smaller foils wholeheartedly, once you get used to smaller foils you learn to utilise their efficiency so using them in smaller and smaller conditions becomes possible. Where I was using the Axis 1300 & 1150 for dock starting I'm now preferring the Kujira 1440, and for pretty much everything else, where I was using the kujira 1210 I'm now using the 980.
Piros has it spot on when he said that the same foil will feel different to other people because of your style and the conditions you're riding in, as well as if it's DW, tow, prone etc, including what tail you use - it all makes a big difference.
There's a few posts here that made me wonder what the hell was going on, like Eppo's post about the kijira being as slow as balls - I'm glad it got cleared up later that he was referring to the 1440, would have been nice to have known that at the start - of course a foil of 1440cm2 will be slower compared to a foil of 980cm2. I think it's well known now that the kujiras aren't the fastest foils out there within their size/performance range (having said that they certainly can't be considered slow by any means) but IMO that's part of the kujira's strength - they seem to be able to match the speed of the waves or swell rather than outrun it which means you can focus on turning when you want to, rather than having to adjust your turns to control your speed or your position on the wave to prevent yourself from outrunning the wave. I also think that the kujira's have been designed primarily as a surf foil and as such they need to be treated in this way if you're going to get the best out of them. Yes they are awesome for downwinding and winging as well, and again IMO this makes them one of the most versatile foils out there - their range of use is just phenomenal, but if speed is your priority in a foils performance characteristics is speed then you'll have to go away from the kujiras - but then you'll be missing out on all the rest they offer that most foils can't match - that lovely surfy feel, drive through turns, ease of pumping at high and low speed, low end as well as high end performance etc etc. I've used the ART 999 a lot as well and although I love it for it's speed, glide, efficiency and pumping, for me the 999 is primarily a DW foil that also surfs and wings very well, whereas the kujiras are surf orientated foils that also downwind and wings very well.
Although I haven't used the Lift HA 120, from what I've heard it beats the kujira 980 in terms of top end performance. From what i've heard it's faster, it turns equally as well (possibly better) it pumps like a beast - BUT it's stall speed is higher so needs to be kept faster to utilise its pump performance, and it's not so forgiving of mistakes. The way I heard it summed up that made most sense to me was that the 120 is best suited to those who want top end performance all the time, whereas the 980 is for those who want a foil that can handle top, mid and bottom range well, and while it may not be master of any, it's damn near close enough! The 1210 and 1440 are equally as good in terms of having such a massive performance range, just on an increasing scale of size. At the end of the day it's down to what your style needs from a foil.

he kujira's strength - they seem to be able to match the speed of the waves or swell rather than outrun it which means you can focus on turning when you want to, rather than having to adjust your turns to control your speed or your position on the wave to prevent yourself from outrunning the wave.

This is a very interesting point. This is what will give the best ratio Glide/effortless which is for me something that matters a lot.

In the Blue Planet interview, I believe Kane DeWilde explained that the aspect ratio of a foil is ascertained by squaring the foil's span and dividing this figure by the foil's area. So if we square the 108.5 cm. span of the 1440 (11,772.25) and divide by it by the area (1440 sq. cm.-- projected area) we get about 8.1:1. I'm not sure how accurate this is due to projected area rather than actual area being used and whether or not these two areas are close to each other (and why projected area rather than the actual area is provided). Using the same calculations the 1210 would have an aspect ratio of 7.1:1 and the 980 an aspect ratio of 6.5.:1. Are these aspect ratios somewhat accurate and if not, why not?

Looks pretty close. Here's the foil comparison google spreadsheet to back that up.

docs.google.com/spreadsheets/d/17xbTGEWSVeRhnYb_4vz_Gmby8UnrDys7Q1iB-6rC6F4/edit#gid=0

Can anyone give me a metric on the Angle of Attack on the kuijira front wing please. I think mine is bent, it's not flying as smooth anymore.

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martyman said..
Can anyone give me a metric on the Angle of Attack on the kuijira front wing please. I think mine is bent, it's not flying as smooth anymore.

I'd like to know this too. I think the arc in the fuse behind the mast has flattened out somewhat coz when I measure the AOI I'm getting over 6 deg. I have had to shim my stab at the back so the AOI is 2.5 now.

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dejavu said..
In the Blue Planet interview, I believe Kane DeWilde explained that the aspect ratio of a foil is ascertained by squaring the foil's span and dividing this figure by the foil's area. So if we square the 108.5 cm. span of the 1440 (11,772.25) and divide by it by the area (1440 sq. cm.-- projected area) we get about 8.1:1. I'm not sure how accurate this is due to projected area rather than actual area being used and whether or not these two areas are close to each other (and why projected area rather than the actual area is provided). Using the same calculations the 1210 would have an aspect ratio of 7.1:1 and the 980 an aspect ratio of 6.5.:1. Are these aspect ratios somewhat accurate and if not, why not?

This is really interesting as I find the 1440 ridiculously easy to pump, the 1210 very easy to pump, and the 980 hard to pump. The pumping I'm referring to is flat water pumping - for downwinding even the 980 is super easy to pump as all it needs is a tiny amount of swell or wave energy to keep it on foil, but for pure flat water pumping I find the 980 looses height on the mast really easily and then it's game over. I wonder how much the aspect ratio affects this - looking at the figures its got to be a big factor. I can't help wondering what the 980 would be like to pump if its aspect ratio was 7 or 8? I suspect it would make it perform more like the Lift HA 120 ????

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Dommo49 said..

dejavu said..
In the Blue Planet interview, I believe Kane DeWilde explained that the aspect ratio of a foil is ascertained by squaring the foil's span and dividing this figure by the foil's area. So if we square the 108.5 cm. span of the 1440 (11,772.25) and divide by it by the area (1440 sq. cm.-- projected area) we get about 8.1:1. I'm not sure how accurate this is due to projected area rather than actual area being used and whether or not these two areas are close to each other (and why projected area rather than the actual area is provided). Using the same calculations the 1210 would have an aspect ratio of 7.1:1 and the 980 an aspect ratio of 6.5.:1. Are these aspect ratios somewhat accurate and if not, why not?

This is really interesting as I find the 1440 ridiculously easy to pump, the 1210 very easy to pump, and the 980 hard to pump. The pumping I'm referring to is flat water pumping - for downwinding even the 980 is super easy to pump as all it needs is a tiny amount of swell or wave energy to keep it on foil, but for pure flat water pumping I find the 980 looses height on the mast really easily and then it's game over. I wonder how much the aspect ratio affects this - looking at the figures its got to be a big factor. I can't help wondering what the 980 would be like to pump if its aspect ratio was 7 or 8? I suspect it would make it perform more like the Lift HA 120 ????

What you're contemplating is the relationship between aspect ratio and the pumping ability of a foil -- you seem to be suggesting that the higher the aspect ratio of a foil the better the potential is for pumping it. I agree. Obviously there are other design characteristics that add or detract from the ability of a foil to be pumped efficiently in flat water over a substantial distance, however, its aspect ratio seems to be one important consideration. No doubt there are many trade offs that designers have to deal with -- what's the main purpose of the foil -- speed, early lift, turning? Something gets compromised. So, the question is -- if you increased the "pumpability" of the 980 by increasing its aspect ratio do you lose somewhere else -- do you takeaway something (like ease of turning) that makes it a great all around foil (something, no doubt, with which the designer of the 980 had to wrestle)? The question really is -- what are you willing to compromise to get a better pumping foil?

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knot2shabby said..

martyman said..
Can anyone give me a metric on the Angle of Attack on the kuijira front wing please. I think mine is bent, it's not flying as smooth anymore.

I'd like to know this too. I think the arc in the fuse behind the mast has flattened out somewhat coz when I measure the AOI I'm getting over 6 deg. I have had to shim my stab at the back so the AOI is 2.5 now.

Im keeping this alive. There are a few of us needing to know this. Kane de wilde aka foilfanatic, can you give us a hand w this?

Angle of Attack as it sits in the fuselage in reference to the rear stabilizer i guess would be the best way-unless there are other suggestions.

Anyone else in the know please feel free to jump in.

Martyman

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martyman said..

knot2shabby said..

martyman said..
Can anyone give me a metric on the Angle of Attack on the kuijira front wing please. I think mine is bent, it's not flying as smooth anymore.

I'd like to know this too. I think the arc in the fuse behind the mast has flattened out somewhat coz when I measure the AOI I'm getting over 6 deg. I have had to shim my stab at the back so the AOI is 2.5 now.

Im keeping this alive. There are a few of us needing to know this. Kane de wilde aka foilfanatic, can you give us a hand w this?

Angle of Attack as it sits in the fuselage in reference to the rear stabilizer i guess would be the best way-unless there are other suggestions.

Anyone else in the know please feel free to jump in.

Martyman

Ideally measure relative to the mast for both the wing and stabilizer. Although that relationship doesn't really matter (it's the relationship between the wing and foil which does) it gives a reliable datum that will let to figure out whether it's the tail or the front of the fuselage which is bent.

I made a homemade "inclinometer" to measure the angle of attack between the front wing and the tail wing. For the 980 and 1210, I run the tail between 3-4deg "up" versus the front wing. The tool I use has v-notches to find the leading and trailing edge centers. As you know this isn't exactly angle of attack, but gives a repeatable baseline.

Regarding the angle from wing to standing deck - I found that the aluminum mast comes setup out of the box was about 2.5deg too much lift on the front wing for my taste, so I shim the baseplate.

I think you guys are talking about AOI's and not AOA's.
Sorry to nitpick but foil talk gets confusing real quick.

AOI: angle between Foil Chord and Longitudinal Axis (in our case we can use mast,or flatt bottom of board,dunno).

AOA: Angle between Foil Chord and Flow (of water for us).

Pitch: Angle between Longitudinal Axis and Horizon.

So mast plate wedging is changing AOA and pitch angle
changing tail angle is AOI

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kobo said..
So mast plate wedging is changing AOA and pitch angle
changing tail angle is AOI

I think you have it,but let me confuse this further :)

If water flow is parallel to board bottom (takeoff) AOI=AOA for both Front Wing and Stab.

Mast plate wedging changes AOI of both Front Wing and Stab.
Which gives you the takeoff AOA of both as the board starts moving.

Tail shim changes AOI+Takeoff AOA of the stab only.
Plus it changes its relationship to the front wing.

AOI is a static measurement, a characteristic of the foil design geometry and your setup adjustment.You can measure it at home.In our case it is fixed once we put the screwdriver away.

AOI's have a big influence on how the foil behaves on takeoff (mostly mast plate shim) and how it reacts to speed changes and weightshifts once up (stab shim).

AOA is dynamic, always relative to the water flow.It changes every instant when sailing.No motion,no AOA.The lift you get from the foil depends on the combination of Speed+AOA.

This concepts may sound confusing for some people and oversimplified for others, but they are fundamental if you want to understand how these thingys work.

You don't need to know any of this,i bet most of the young rippers out there don't know or care, but for me it helps to setup gear with less hours of trial and error or to improve riding technique.Gifted athletes just go :)

Foils are simple but not intuitive to understand, this are just the basics and they are hard enough to put into words.Hope i have not screwed it up...

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jondrums said..
I made a homemade "inclinometer" to measure the angle of attack between the front wing and the tail wing. For the 980 and 1210, I run the tail between 3-4deg "up" versus the front wing. The tool I use has v-notches to find the leading and trailing edge centers. As you know this isn't exactly angle of attack, but gives a repeatable baseline.

Regarding the angle from wing to standing deck - I found that the aluminum mast comes setup out of the box was about 2.5deg too much lift on the front wing for my taste, so I shim the baseplate.

Thanks Jon. Don't you mean your run the stab 3-4 down vs the front wing? i.e leading edge angles towards the seabed? If the stab was pointing to the surface more than the front wing it would probably ride really weird?

Select to expand quote

jondrums said..
I made a homemade "inclinometer" to measure the angle of attack between the front wing and the tail wing. For the 980 and 1210, I run the tail between 3-4deg "up" versus the front wing. The tool I use has v-notches to find the leading and trailing edge centers. As you know this isn't exactly angle of attack, but gives a repeatable baseline.

Regarding the angle from wing to standing deck - I found that the aluminum mast comes setup out of the box was about 2.5deg too much lift on the front wing for my taste, so I shim the baseplate.

Jondrums, you have a grip on wjats going on. Could you please provide me the factory AOA-AOI of the wings, based off of a zeroed out angle finder at the base of the plate?
It would help toomuchepoxy, myself and a few others no doubt.
If so, are you using long calipers to get the front wing angle as I am?

I did a dw run (sup) with a friend from tahiti (big guy), he's got a Kujira 1440, he was going really fast (21km/h average) 30 top speed.
I use a shim, always with 1440 and 1210.
For my weight I like it on light wind but looks like bigger guy can get the most of it on good condition.

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frenchfoiler said..
I did a dw run (sup) with a friend from tahiti (big guy), he's got a Kujira 1440, he was going really fast (21km/h average) 30 top speed.
I use a shim, always with 1440 and 1210.
For my weight I like it on light wind but looks like bigger guy can get the most of it on good condition.

Carbon mast or the new aluminum? Do you shim the plate or the back wing?

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dk78 said..

frenchfoiler said..
I did a dw run (sup) with a friend from tahiti (big guy), he's got a Kujira 1440, he was going really fast (21km/h average) 30 top speed.
I use a shim, always with 1440 and 1210.
For my weight I like it on light wind but looks like bigger guy can get the most of it on good condition.

Carbon mast or the new aluminum? Do you shim the plate or the back wing?

2021 Alu mast, shim front of the plate.

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frenchfoiler said..

dk78 said..

frenchfoiler said..
I did a dw run (sup) with a friend from tahiti (big guy), he's got a Kujira 1440, he was going really fast (21km/h average) 30 top speed.
I use a shim, always with 1440 and 1210.
For my weight I like it on light wind but looks like bigger guy can get the most of it on good condition.

Carbon mast or the new aluminum? Do you shim the plate or the back wing?

2021 Alu mast, shim front of the plate.

I haven't tried any shims yet. I have moved the mast (which was at the very front of the track) back 1 1/2 to 2 cm. and found I had more control in higher winds.

Most of the guys during the sup foil dw french championship didn't use any shim for 980 or 1210. The 1210 seemed to be the best all round foil, the speed range, being from really low to really hight is very impressive.

oh ya.

Interesting^^^, have you noticed any difference in the way it rides compared to the stock Takuma setup (mast set further back from front wing)

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toppleover said..
Interesting^^^, have you noticed any difference in the way it rides compared to the stock Takuma setup (mast set further back from front wing)

Should be less front foot lifty if it's anything like the old SS gear which had A,B,C mast settings on the fuse. The further back the mast is on the fuse the more front footed it will be and very noticeable.

I tried today the 1210 (85cm mast alu and new stab) for sup dw. I did two short run to test it.

First run without shim : I didn't like it at all, way too much back foot, too much nose down. Hard to get up.
Second run with a shim (shim under font plate) : way better, easier to get up, less back foot.

Now I need to try with another rear wing, this one feels too loose, not enought drive for dw.

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toppleover said..
Interesting^^^, have you noticed any difference in the way it rides compared to the stock Takuma setup (mast set further back from front wing)

the response is way better. where we are in the surf we have a river that spews out a lot of current. The flimsy takuma alum mast was just not up to task, it would wobble around like a noodle. Axis mast-stiff and ultra-responsive. The difference is significant.

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martyman said..
oh ya.

Just need to make a fuselage which accepts the Starboard rear piece to have the best of all worlds.

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frenchfoiler said..
I tried today the 1210 (85cm mast alu and new stab) for sup dw. I did two short run to test it.

First run without shim : I didn't like it at all, way too much back foot, too much nose down. Hard to get up.
Second run with a shim (shim under font plate) : way better, easier to get up, less back foot.

Now I need to try with another rear wing, this one feels too loose, not enought drive for dw.

What rear wing were you using please Greg?