Foil size for heavy rider

[Abaltasis]

I am an advanced TT rider at around 115kg.
I can ride my TT with my 12m kite from around 15knots and up, but as a seasoned rider i am very picky and i dont bother to get in the water if its not at around 20knots and up.

So... my goal is to learn to ride a foilboard at the 12-to-20knot range with my 12m kite (or maybe the 10m ?), until the wind picks up to get my TT
I state this because i know that foilers usually want to get foiling from single digits wind speed.
I wont be riding in less than 12-13 knots because here in Greece, we usually have strong winds all year, and we usually dont bother if its really low.

So... most of the info i find on the internet say that for a rider who is beginning to foil needs a foil wing of around 800 to 1000 square cm. (less than that is the racing category?)
But also i see the wings from many companies go up to 2000sq.
From what i see the bigger the wing the slower it gets but also the easier is to get up? is this true?
and if it is why then they say for beginners only 1000sq and not bigger than that?

What would you recommed for a heavy rider?
Thanks

[Kamikuza]

Depends what you like. I demand as little flex and wobble from my gear as possible so I'm using a setup with 19mm mast.

I don't like really wide wings so I'm using 660mm wide 1200cm2 wing and an 8m kite...

But that's just me.

Bigger tends to be slower.
Higher AR tends to be more difficult to ride.
Wider tends to be more stable.
Bigger also gets on the foil sooner so you need control sooner...

You want to be able to ride the foil board on the surface of the water and let the board speed raise the foil.

So you don't want a huge foil to start with. 800 would be too small at your weight IMO. I'd suggest an Axis 680 with 400 stabilizer on a 16mm 82cm mast...

[Peter_Frank]

Kamikuza is right.

Except I find an 1120 cm2 wing (Axis 680) a bit small
(unless this very one has an extra thick cambered profile of course)

But if you think you like to go fast, and still have a fun turning wing, it is fine with this size.

1120 cm2 not too high aspect, is the most used allround size today, for average weights.

Meaning, if you use this size, it would correspond to a 750 cm2 wing for an average weight, which is very small.
It doesnt quite work this way, as you also use a bigger kite, when heavier, which takes some of the load.

But unless you know you want to go fast, I would advice to seek something around 1200 to 1400 cm2.
And even bigger if you want to surf around in small wind chop waves or medium waves

Peter

[Frankieboy]

I learned with same weight with a 600cm2, then went up to 900 and 1200cm2
Currently riding my Moses 633 (1250cm2) and use the 790 (1550cm2) also but for very specific use like wave riding with the peak for instance.

So I would say don't go bigger then 1200cm2 it doesn't have any added value. If you want to carve, the Moses 633 is perfect, if you want more speed take a thinner front wing

[Abaltasis]

Thanks guys.
So you all agree that the optimal for beginner is about 1200-1300sqcm.

And probably a 70-80cm mast...
But should i check the mast width? Kamikuza you said 19mm mast. Does this have a big effect if its 16mm or another?

Also one last question which i cannot seem to find an answer...
Does all foilwings are compatible with another company foilboards??
An axis wing can go to a duotone or cabrinha board?
Or whatever companys wing with whatever companys board?

[Kamikuza]

Thanks guys.
So you all agree that the optimal for beginner is about 1200-1300sqcm.

And probably a 70-80cm mast...
But should i check the mast width? Kamikuza you said 19mm mast. Does this have a big effect if its 16mm or another?

Also one last question which i cannot seem to find an answer...
Does all foilwings are compatible with another company foilboards??
An axis wing can go to a duotone or cabrinha board?
Or whatever companys wing with whatever companys board?

Depends. 660 is more aggressive lifting profile than the 680, so it has range more like my 820. Depends on the wing design, eh.

19mm feels a tad slower through the water, but it's less important to me than how much more rigid it is. At your weight, something like the Axis 16mm will be fine, don't know if other brands offer width options.

If it's a plate mount foil, then I'd assume it'd fit any modern board with tracks -- everyone sorta standardized the width, but most manufacturers post the specs anyway. I'd only worry if the board only had holes and not tracks.

I ride a 2020 Axis foil on 2017/18 Slingshot board. I doubt wings or stabs can be mixed with other manufacturer's fuselages though ... even masts and plates are most likely not compatible.

[joriws]

I am 5kg lighter and use Sab / Moses 633 or 790 depending on mood with 91cm mast. No problem going in the winds mentioned even with 5m Peak4. Lower the wind gets it is just harder to get from water to board (10-20l range) but once foil is flying no problem.

If board tracks are 9cm (from memory, check the specs and only buy from manufacturor which releases exact specs) apart (us box) then you should be able to use any board.

[Windigo1]

I find that the rider weight doesn't make much difference on a foil I have been out with heavier riders than me on the same wing (Moses 633) and everyone was able to ride with similar size kites in different wind conditions the smaller riders have an advantage in very light wind but the difference isn't huge like on a twintip.

[drsurf]

I find that the rider weight doesn't make much difference on a foil I have been out with heavier riders than me on the same wing (Moses 633) and everyone was able to ride with similar size kites in different wind conditions the smaller riders have an advantage in very light wind but the difference isn't huge like on a twintip.

I agree with the above.

I'm 65kg and have a 100kg customer who has the identical board and Moses 679 foil set. I have been out on my 4m Peak4 kite just comfortably powered and he has been on an identical 4m Peak4 kite and being also just comfortably powered and riding easily.

I was quite surprised at how little difference there was between our weights. I'd say there would be only a knot or two of difference between the two of us getting going in light winds. The Peak4 kite does seem to make it a bit easier. I have sold a number of Peak4 kites to beginning foilers and they have found them much easier to use especially in lighter winds where they don't fall from the sky in lulls and the power delivery is smoother.

[Peter_Frank]

Actually quite fascinating, and agree the difference is not very big.

If we got a 50 kg and a 100 kg rider, then you need twice as big a wing, to be able to ride with same (low) speed, if not using a kite.

What happens though, is IMO 3 things:

1. The heavier rider will ride a bit faster, thus getting sufficient lift from a wing not twice as big.
2. The heavier rider will use a bit bigger kite, and riding a bit faster, apparent wind gives more kite lift also (just like the wing gives more lift).
3. The heavier rider needs a bit more wind - but as lift is exponential to windspeed, windspeed 8 knots for 50 kg is same kite lift as 11 knots for 100 kg so not "twice as much wind".

All three things combined, gives the impression there is hardly any difference, as a subtle increase in each means you ride in the same wind

But there is, difference, so if you want to surf at same low end speed say with a drifting not loaded kite, you need a bigger wing for a bigger rider.
Or in terms of "How low can you go", weight matters.

Also, just like with a TT board, most heavier riders dont want too big a wing (or board or kite), as it will become slower to turn and handle.
Eventhough they got more strength and weight to handle bigger gear.

Another special thing is, the glide angle is the very same, no matter if light or heavy, you just go faster if heavier, but you can ride a wave more angled (diagonal) because you ride faster, than a lighter rider can, but you need (to extract) a bit more power from the wave.

A rider twice as heavy (100 % heavier), will only have a "sink rate" 41 % higher (and not doubled), because the riding speed is also 41 % higher, meaning twice as much lift.


This is why the differences light/heavy are more subtle than one would think

Peter