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Floyd
14th October 2008, 05:46 PM
Hi
Isnt it time some kind of allowance/explanation was made on site for variations in rider weight for wind range of various boards.
For example the kode 86 is quoted as having a windrange of 4.0 to 6.0(sail usage).
Now I`m pretty sure the board would not be ideal when coupled with a 6 metre and my 95k rider weight.
On the other hand I do think the Kode 102(sail range 5 to 7.5) would work quite well with a 4.5 when carrying 95k plus.
Neither of these "opinions" are born out in specifications.
My own Evo 92 works great (for me) easily down to 4 metre but struggles with anything over 6. (sail range 4.5 to 6.5)
It could lead to heavier riders buying wrong board or not buying a board that could be ideal. ( heavier mate of mine has a fantasic time on kombat 105 in 4.5 weather;which I think is out of "ideal range" of board.
Whats teams opinion on rider weight affecting board range ???

Does heavier rider decrease both upper and lower limits ? (ie range is same) I think it does???

Ola_H
14th October 2008, 07:23 PM
My take is that both upper and lower sail ranges of a board changes with rider weight. Of course, other things, like sail type, skill and preference might have just a big an effect, but for a "given" rider (conceptually speaking, one given rider can not, at least not at the same time, have more than one weight) sail range vary with rider weight.

But in my experience, it is not as easy as a simple shift. This follows from another fact, namely that for a given board type and saior, there is often one board size that give the maximum sail range. A bigger board will loose more on the high wind side than it will gain on the light wind side. And vice versa with a smaller board.

But the question is of we should create som kind of schemata showing this? I'm not sure its such a good idea since there are also all the other variables (skill, preference etc) that is kind of hard to quantify. Maybe a sensible way to do it is to just hint that the rec sail sizes are just indications for a "general" rider.

Jean-Marc
15th October 2008, 01:24 AM
Agree with Ola : too many variables are at play to simply feed everything into a 2 dimensional table. The same gear may not work as good as intented for a super light/light/medium/heavy/super heavy weight rider simply because the wind range is shifted toward more high wind with increasingly wind force and rider weight. Optimal balance and trim between rider weight, wind force, sail size, fin size, board's and sail's shape is almost endless with a single and unique gear.

I believe rec sail size are given as an indication for an average rider's weight of 75 kg.

Cheers !

JM

Floyd
15th October 2008, 04:57 PM
Which is fine if you happen to be an average weight rider.(Whatever that is?)

I agree an explanation and or a table would be overly complicated and probably confuse the issue even further but the simple fact is that the quoted windranges (guide or not) are infact wrong for many riders.

We do this every time more objectivity is called for.Fog the issue with statements about variables and complications.(Heard same argument for measurment of sail sizes;mast stiffness;board volumes etc etc) Its what we always say.(Then go on about rider experience;application; etc etc) We introduce the variables to further the argument !

At my sailing weight (about 103k) I`ve learnt to ignore manufacturers guides.I find them out myself ! It normally leads to some "expert" (lightweight ; both senses of word) approaching on beach and reminding me that the k105 isnt really good for sails under 5 metres. Sorry it is !!!Its superb ! (For me) (To be honest I find it better in 5 metre weather than Evo 92.(or perhaps better suited to my weight/skill/conditions etc etc)


It really has to be blowing hard and constant for me to get any benefits from going smaller.
That is not born out in guides.
If I followed guides (for wind ranges)I should be on perhaps Kode 80 ? (for 5 metre days)
By experience I still need(or its nearer "ideal") around 95 litres on 5 metre days.
Perhaps its just me ????
What do other 100k+ riders use in 5 metre weather ?

choco44
16th October 2008, 05:46 AM
Interesting question, i was visiting my brother in law in Melbourne last week who is a keen cyclist,he took me down to his local bike shop and showed me the latest carbon bikes($10,000+).
We then watched a guy being "fitted" to a bike he wanted to purchase,his bike was setup on rollers and a computer system setup with cameras and sensors and the guy simply rode the bike and they made changes to the seat post/added longer neck to the handle bars etc until it was setup to his own body style.
It would be very easy to create a fitting system for windsurfing boards and sails! a simple program which takes in height, weight,type of sailing,harness line length,fin size,board volume etc and wind range would help people go a long way in choosing the right setup for the wind range they intend to sail.
People love technology

Jean-Marc
17th October 2008, 02:20 AM
Floyd,

I don't agree with you that the wind range of boards are at best misleading or worse, deliberately wrong.

Some example. A 105 kg pal is using a Carve 162 + 52 cm stock fin + 9.5 sail in 12-18 knots of wind. I would be using such a combo in 7-12 knots of wind for my 65 kg; for 12-18 knots, I'm on a Kombat 86 + 30 cm fin + 6.9 sail.

Is the wind range of the Carve 162 above wrong ? Is it wrong to say that the Kombat 86 cannot be used by a 105 kg pal as of 12 knots of wind? Of course not... rider's weight does matter.

Just from the guesswork described above, one can estimate that a rider would need 1m2 of more sail surface for each 10 kg more of body weight.

Things get more complicated for a sinker : I need 20 knots of wind to get planing with an Acid 62 liters + 5.4 m2 sail but I strongly doubt it will be the same with my 105 kg pal. Is the wind range of Acid 62 wrong ? Of course not...BTW, Acid 62 rec sail starts at 4.7 m2, something certainly valuable for an average 75 kg rider but not necessarily true for a 65 kg rider.

Conclusion : wind range are an indication given for an average rider weight of 75 kg. My guess is that such a figure is the world average weight of a 30 years old male population according to some WHO (?) statistics. Average male weight is of course higher in USA (i.e., due to higher incidence of obesity) and lower in Thailand for example. Hence the choice of an average rider's weight to get a reference at some point in the big picture.

Would you have a better proposal as a rider's weight reference ? Why ?

Cheers !

JM

Jean-Marc
17th October 2008, 02:36 AM
Choco44,

I don't think an one-size-fits-all computerized system will solve the problem. I just love using extra long 32 inches long harness lines with a race seat harness + lower hook with my 2 largest racing sails. I'm using 28 inches long harness lines with either small racing sails + race seat harness or small wave sails + chest harness + higher hook.
These are typically 4 variables (harness line lenght, harness type, hook hight, sail type) a computerized system cannot take into account just for everybody. I'm pretty sure another 65 kg x 183 cm rider will use a completely different setup with the same gear (some of my friends do like extra long harness lines, other just hate them. Same with chest harness or race seat harness, some just love waist harness).

Cheers !

JM

Floyd
17th October 2008, 05:06 AM
Hi Jean-Marc
I never said they were deliberately wrong.
I said they were wrong for a lot of riders.Obviously they are fine for many.
Just think there should be allowance mentioned/made to indicate that in some instances (generally for riders towards either extreme of weight) the ranges quoted may well be innapropriate.
Its pretty well accepted heavier riders cant carry as big sails (on smaller boards) yet they can use biggish boards with under the minimum rig size quoted.(with sufficient wind)
Read on some other thread today about Ian Fox saying he prefered (dont quote me on this I`m trying to remember exact statement) I think it was k95 over k85 in 5 metre weather; the k95 was in theory out of its sweet spot on sail size and 85 exactly in it.

If the ranges are correct how come so many sailors do sail well out of them ? Like I mentioned earlier my Evo 92 with 95k+ on it does NOT work in any way you could call ideal with over a 6.Yet it works fine with a 6.4 carrying 65k.There is simply no mention of this anywhere on SB`s site !

Boards DO have different wind ranges for different weights.(Pretty obviuos really !)

mim
17th October 2008, 05:35 AM
Hi,

I just have to ask again why does it matters so much? All of you guys writing to this thread have more than one board, rigth? And as you bought your first board you discovered what is the favourite sailsize for the particular type and volume...and if you want to go down or up you take a look at the range given by SB and you go for a board having the same sail range (relativly)...so what for is this forum...and the reply just to know why, or to help people without any experience....this is not helping, at least I think so.

There was already mentioned that all other things are important.
Everyone who buys a new board gos and try in the conditions what it was made for and if he realize that the sailsize is not OK, take another one. And if there is not other one...only thing that left is to try harded and donīt give up to learn how to use it with the sails you have.

And I have to add one personal thing...there are days that I go with the biggest sail for my Aero 117 or smallest sail (or even smaller) for ST137 and I like it. And there are days when I do opposite and it is better that way. It depends strongly on spot, waves, chop size and orientation, if the wind is gusty or not etc.

I am not lightweight (in neo...95kg). And observed that it very much depends on conditions than on a sailsize.

Ciao Michal.

Floyd
17th October 2008, 10:21 PM
Mim
Going on interest in this thread there are a lot of folk interested in relationship between rider weight and a boards windrange.
Wont say the obvious.!
Take care
Windy tomorrow !

mim
18th October 2008, 03:14 AM
Floyd
It is clear to me. I just say, there is a weigth dependence of a board wind range. I always check the windrange only roughly and finally I go to get the board that have the feeling should be exactly what I wanted.

What I was trying to say...since the windrange depends strongly on all the conditions, even if you say that the weight is an important thing it is not the only one...and buying a board just blindly is a bad idea...and when you yourself nor realise that the sail that you are using is out of range than you have not the technique well.

In fact I do not look at the sail range data too much, I check the other parameters, volume, max width, tail width...and I decide whether it is what I want or not.

Sailrange for me is only rough number...and i guess it always will be!

PS: I am thinking too much since there is no wind. Rather be on water than on forum :(

Ciao Michal.

Jean-Marc
18th October 2008, 04:44 PM
Floyd,

I guess the same problem occurs with "5 meters weather". To whom this reference would apply ? Some example: last month, wind was blowing 24-30 knots on our lake. For me, it's typical 4.7 meters weather on a 62 L wave board. For a 98 kg pal, it's typical 6.2 meters weather on a 95 L wave board.

Same wind but different gear for different rider's weight:

a) Could I use K95 with a 4.7 sail? Sure. Is it fun? Nope, way too big a board. Could I use K86 with a 4.7 sail? Sure. Is it fun? Yes, but still too big a board to play in the swell. Could I use A62 with a 4.7 sail? Sure. Is it fun? Oh boy, it's perfect in the swell !

b) Could the 98 kg pal use K86 with his 6.2 sail? Yes. Is it fun? Nope, too much sinking time in the lower wind range. Could the 98 kg pal use K95 with his 6.2 sail? Sure. Is it fun? Yes, best compromise between manoeuverability in the swell and schlogging in the lulls. Could the 98 kg pal use Aero 127 with his 6.2 sail? Sure. Is it fun? Yes, but still too big a board, less playful in the swell.

c) it's "5.4 meters weather" in 20-25 knots wind for me and I can choose 4 boards as follows depending on the conditions:
Speed on flat water: HS105 > Carve111 = Kombat86 > Acid62
Fun at wavering or B&J : Acid 62 > Kombat 86 > Carve 111 >>> HS105

Conclusion 1: choose sail size according to wind and rider weight.
Conclusion 2: choose board size according to wind and rider weight: too much volume a board is unecessary ballast, too wide a board hinders its manoeuverability in the swell and not enough volume/width increases sinking time while schlogging.

Cheers !

JM

Floyd
19th October 2008, 05:21 PM
Hi JM
Thik we are nearly agreeing ???
If I remember correctly your weight is circa 70k ?
For me the k95 was perfect in 4.7weather. (and below /stronger)

There has always been a atmosphere of pushing riders onto smaller boards ;fine if rider weight is considered.
Dunkerbeck was using 97 litres in 4.7 weather when I saw him sailing.
How many 95+ litre boards do we see as been usable (ideal) in sub 5 metre weather ?

Emporically I reckon each 10k body weight reduces minimum sail by perhaps half a metre ?

peterggg
28th October 2008, 05:41 AM
I find that a good weight / conversion is to compare directly kgs to ls. I'm 100kgs and I basically never sail anything smaller than my weight (I take out my girlfriend's 96l light-wind board for nuking Gorge days). The rest of the time I'm happier on my Carve 111 because in our flukey winds I can uphaul it and still get home in 5 knots (though thigh deep on the uphaul). My question for the experts, though, is:

what are 100kgs sailors meant to do if they want true freestyle or wave boards for lighter winds? I was very excited to see the Kode was a freestyle wave at 122 l only to discover that at that size it is actually a freeride slalom.