Hey guys,

Does the kite make much of a difference in max speed of a foil?

Recently went out on a 12 mono, and tried aluminium mast / carbon race mast / low wind foil, ultra low wind foil , high wind high aspect race foil, and smaller fuselage - all same day / conditions 10-14kts

Now I think... the mono is stopping me going over 21 its, because I got the aluminium foil with low speed wing up to 20.8, and the race foil to 21.7kts.

I couldn't go any quicker because more kite power needed me to lean back to balance, but leaning back was making the board climb.....

Would this be due to too big a kite in the wind, or the low aspect of the mono? Anyone else notice top speed differences because of the kite ?

Yes, the kite used will effect top speed. I went down the same path, my surf foil with mono strut kites was good to about 18 knots. I bought a race foil but was topping at about 20knots with the same kites.
i find as you going faster you having to push the bar out as the kite becomes more powered due to the apparent wind increase. This is when I'm feeling more flutter from the kite, so drag must be increasing too.
I have since bought an Ozone Edge as an experiment, a lot better, hit 22 knots easily with little flutter but they are a heavy kite which is a major draw back in lighter wind. I'm sure with more experience top speed will increase with this kite though a high aspect foil kite is probably a better option due to light weight and refined airfoil.

Might be also the size of the kite as my 8m single strut had me around 24 knots. As measured by a windsurfer with gps running beside me. He was on 24 knots but said I was slightly pulling away.
But im not going down that scary track again.

hi mate,almost any higher aspect kite can do 40knots. Only 2-3 foils can tho!

We been doing over 35knots downwind on the new KFA Mako3 foil with 112cm mast. Good rush

I have stupid high to stupid low aspect kites in my range. chrono, edge, catalyst, reo, uno.

The chrono goes fast as F u c k
Uno... not so much. I i can still go plenty fast!

What limits me more is the water condition. Lumpy as sea is real hard to go stupid fast..

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INTHELOOP said..
We been doing over 35knots downwind on the new KFA Mako3 foil with 112cm mast. Good rush

Marv, what speed can you do same foil on the mono ?... and if I said what race kite size would you pick for max speed in 12 ts, nothing to do with upwind or downwind, just max speed?

Hey Dachopper,

Top speed is more dependent on the foil more than the kite. The fastest speed run on the compass is usually around 130 degrees off the wind. Power from the kite doesn't determine maximum speed unless you are under powered. A tube kite will deliver more power than you can use as can a foil kite.

The difference foil kites make is when you are running in less than ideal vectors, ie going deep downwind or "pinching" upwind. The foil kite will generate more power and at higher angles into the wind than any tube kite when pinching, but upwind is never going to give you maximum speed. The foil kite will also go much deeper downwind with much better power and efficiency than a tube kite due to their lighter weight and more aerodynamic profile which gives less drag allowing you to go faster.

I use mostly foil kites and only ever change to a tube kite if wave riding or I'm too overpowered on a foil kite. The other difference between foil kites and tube kites, is due to their efficiency and lack of drag, they don't de-power nearly as much as a tube kite. This could be one reason why people trying foil kites initially feel that they are faster, because it is very difficult to slow down when you can't shut off the power on a foil kite.

Without a doubt, foil kites are better on most points of the compass but in the fastest angle, either kite will more than do the job. Looking at the Namibia Luderitz speed challenge, almost no one uses a foil kite because enough power is never the problem, it's the board or in this topics case, the foil under the board.

A fully de-powered foil kite can be unstable in strong gusty winds when high in the wind window, inversions can happen.

The issue you describe is also probably more to do with the max speed of the foil and your riding position. As most foils go faster, they generate more lift, which in turn requires more front foot pressure to keep the lift in check. You need to keep weight out over the edge of the board, but not back, it is an awkward riding position to go really fast, hips thrust forward, front knee bent and back leg straight. (See pic below)

Having said all that, if you are under-powered, yes, a foil kite will be more efficient and more powerful than a tube kite. My best speeds are usually around 2.5 times wind speed, I'm guessing that's the limit of kite efficiency and this is usually when I am comfortably powered and not over powered. I ride the 2018 North Ace's and Moses 2018 Comet board and foil.

Hope this helps.

DM

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ActionSportsWA said..
Hey Dachopper,

Top speed is more dependent on the foil more than the kite. The fastest speed run on the compass is usually around 130 degrees off the wind. Power from the kite doesn't determine maximum speed unless you are under powered. A tube kite will deliver more power than you can use as can a foil kite.

The difference foil kites make is when you are running in less than ideal vectors, ie going deep downwind or "pinching" upwind. The foil kite will generate more power and at higher angles into the wind than any tube kite when pinching, but upwind is never going to give you maximum speed. The foil kite will also go much deeper downwind with much better power and efficiency than a tube kite due to their lighter weight and more aerodynamic profile which gives less drag allowing you to go faster.

I use mostly foil kites and only ever change to a tube kite if wave riding or I'm too overpowered on a foil kite. The other difference between foil kites and tube kites, is due to their efficiency and lack of drag, they don't de-power nearly as much as a tube kite. This could be one reason why people trying foil kites initially feel that they are faster, because it is very difficult to slow down when you can't shut off the power on a foil kite.

Without a doubt, foil kites are better on most points of the compass but in the fastest angle, either kite will more than do the job. Looking at the Namibia Luderitz speed challenge, almost no one uses a foil kite because enough power is never the problem, it's the board or in this topics case, the foil under the board.

A fully de-powered foil kite can be unstable in strong gusty winds when high in the wind window, inversions can happen.

The issue you describe is also probably more to do with the max speed of the foil and your riding position. As most foils go faster, they generate more lift, which in turn requires more front foot pressure to keep the lift in check. You need to keep weight out over the edge of the board, but not back, it is an awkward riding position to go really fast, hips thrust forward, front knee bent and back leg straight. (See pic below)

Having said all that, if you are under-powered, yes, a foil kite will be more efficient and more powerful than a tube kite. My best speeds are usually around 2.5 times wind speed, I'm guessing that's the limit of kite efficiency and this is usually when I am comfortably powered and not over powered. I ride the 2018 North Ace's and Moses 2018 Comet board and foil.

Hope this helps.

DM

Thanks mate - that all makes a lot of sense....

I think ,my problem might be that I was trying to hold ~ 60 - 90 off the wind, rather than following the kite down, and when the kite powered in that position, the balance point of the kite was moving behind the balance point of the board.....

Do you have to crank the board over for a comfortable higher speed? or is it easier to just have a little lean ???

The fastest speed on any wind powered thing is going to be a curving arc downwind. The faster you go the further back the wind window shifts. You have to arc down wind to compensate for that or your kite will reach the edge of the new wind window and that will be your maximum speed. For course for any wind speed, kite, board combo there is a sweet spot for where the fastest speed can be obtained. No matter what you do you cant go faster than that unless a variable changes,


Higher aspect kites can point further forward in the window so they can arc down wind further before they reach the limit. In truth its only a few kph faster than a lower aspect kite in the same winds.

Regarding being canted over for speed, on a foil I find a down wind speed run i am canted slightly. I am not canted like the photo above which is most likely a high speed upwind tack. Too much cant and you will slow down, not enough cant and you will potentially be unstable. You need to find that ballance point of speed V stability.

Hi dachopper,

In order to hit a V max, the best way is to 90 degrees to the wind initially with a moderate lean on the foil. Sheet in and allow the power to pull you more downwind rather than letting the bar out. Go with the wind and ease up on the leaning of the foil, you don't need much pressure against the foil. By keeping the foil kite, sheeted in or even slightly over sheeted, you can drop it further back into the apparent wind window and then edge a little whilst easing the bar out for maximum speed.

Going from 20 knots to 25 knots is easy, little effort required, going from 25 knots to 29 knots takes a fair bit of concentration, skill and gear. Going from 29 knots to over 30 knots starts getting really intense. Intense concentration, solid locked in stance, 100% commitment and your gear will need to be absolutely on pointe. Going into the mid 30 knot range you'll need to be on race gear, have the mast and wings properly filled and sanded, no blemishes, pin holes or nicks. You will also need huge plums. Confidence is everything over 30 knots.

I've managed almot 32 knots and started having ventilation issues or feint of heart issues usually resulting in some horrendous crashes.

I love speed and have made 35 knots my target for this season. Very excited to see some nice steady breezes again. If you want to try some faster foils, come up or meet me at the river one afternoon and I'll bring some foils along you can try.

DM

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ActionSportsWA said..
Hi dachopper,

In order to hit a V max, the best way is to 90 degrees to the wind initially with a moderate lean on the foil. Sheet in and allow the power to pull you more downwind rather than letting the bar out. Go with the wind and ease up on the leaning of the foil, you don't need much pressure against the foil. By keeping the foil kite, sheeted in or even slightly over sheeted, you can drop it further back into the apparent wind window and then edge a little whilst easing the bar out for maximum speed.

Going from 20 knots to 25 knots is easy, little effort required, going from 25 knots to 29 knots takes a fair bit of concentration, skill and gear. Going from 29 knots to over 30 knots starts getting really intense. Intense concentration, solid locked in stance, 100% commitment and your gear will need to be absolutely on pointe. Going into the mid 30 knot range you'll need to be on race gear, have the mast and wings properly filled and sanded, no blemishes, pin holes or nicks. You will also need huge plums. Confidence is everything over 30 knots.

I've managed almot 32 knots and started having ventilation issues or feint of heart issues usually resulting in some horrendous crashes.

I love speed and have made 35 knots my target for this season. Very excited to see some nice steady breezes again. If you want to try some faster foils, come up or meet me at the river one afternoon and I'll bring some foils along you can try.

DM

I wish I could, I work in the sandpit - only back in Perth for a couple weeks a year..... around the Lancelin Ocean Classic time next year hopefully ;)