View Full Version : Fin too big?

7th June 2011, 04:14 AM
Hello Roger,
thanks for all the advice you gave me last summer :) I was very happy with my Rio S and NCX 8 until I took my husband's Futura 133 and NCX 6,5. I fell in love with that combination immediately. Even though it was not me in command... The board really wanted to get planning (wind was maybe 12-14 knots) and I was able to hang on hooked on harness and front foot in the strap. No catapults this time but absolutely not that stylish riding.

The smallest fin we have is the 48 cm slalom fin that came with the board. Is it too big for FU 133 + 6,5 NCX (my weight 60 kg)? It was easy to go upwind and it planed easily but it was a bit difficult once the speed got up and I was trying to get my feet into straps. I guess you could have seen the Tiki-guy in the bottom of the board no matter where you were standing, the board turned in to every direction before it settled down and started going (there was a man on the beach that couldn't watch my rodeo ride :D)

Long story but here is the question: is it any good to ask for Santa Claus for a smaller fin or should I just be happy with that 48 cm fin and keep practising?

Our spot is a lake with gusty and not that strong wind.

Thank you in advance and have a nice summer!

7th June 2011, 01:25 PM
Hi *MC*
The fins that are supplied with most Starboards are pretty much "in the middle" as far as the fin range
for that board goes.
So, if a 48 cm fin came with your husbands Futura 133, the true fin range is probably 4-6 cm on either side of 48 cm.
So, 52-54 cm would be great for light winds and large sails (like 8.5 m2) and conversely 42 cm would not be too small for a 6.5 m2 rig.
So, yes, a 42 cm should work, but I suspect that you need to do a little more learning/training on fin control.
My guess is that you are probably a lightweight (most girls are) so try to find a 42 cm fin and
also try to learn better control.
If the board is "turning over" when you try to get into the footstraps, my guess would be that you are not getting your back foot place correctly over the centerline just ahead of the rear straps while you get into the front strap.
That back foot is all you have to "steer and control" your board, so it has to be placed correctly to give you that control.
Hope this helps,

7th June 2011, 02:43 PM
Thanks for the very polite answer (can't see myself "lightweight" with my 60 kg's but now that you can't see me, "girl" sounds so lovely for a bit older lady like me :-))

What you said about the back foot is so true; I didn't even remember that I have two legs when concentrating on the front strap. Next time less screaming and more control (I have to add that word to my windsurfing dictionary).

I was told to put my both feet into the straps before harness but with my skills I have to hook on the harness first, otherwise I can't get speed enough and then with a slight panic (catapult in mind) get my foot into the strap.

One more question: do you think it's easier for me to learn with that 48 cm fin than 42 fin? Is it more demanding with smaller 42 cm fin? Or do you mean that 42 cm fin is still "big" and more advanced could go for even a smaller fin? I'd like to get the combination that is the easiest to handle. I don't mind if the big fin makes my ride slower. Like you said, my goal is the control - not the speed :-)

I'd really appreciate if you had patience to answer these questions :-)

8th June 2011, 11:34 AM
Hi MC,
Awww... 60 Kg. (132 lbs.) is not all that heavy for a more mature "lady", right?
Try the 42 cm fin.
Depending on your sail size, you will perhaps want to switch back and forth between the 42 and 48.
If you are well powered up.... use the 42 cm.
If you are having a hard time getting planing.... use the 48 cm.
Either fin will be "easy to handle and control" if you choose the fin that suits the conditions and sail size.
Hope this helps,

10th June 2011, 02:22 PM

i actually use a 40 cm fin with my 7-oh
as a heavyweight, i really like this combination
so, ideally, even for myself , i would choose under 40 cm fin for 6.5 in an ideal world, butt since i have the 40, i would use that

since you are 40 kg lighter than me, i imagine under 40 cm would be great also
perhaps 38 cm fin, if there is such a thing ??
i find a bigger fin with a small sail is okay until the wind picks up
then the board gets too much lift and creates issues of "control"
people do not seem to pay enough attention to the board, sail AND fin combination
some speed sailors have dozens of fins - to get just the right feel for the combination and for the day's conditions

roger: is there a "significant" difference between 38 and 42 cm for a lightweight like the "lady" here ??


10th June 2011, 10:24 PM
Hi Joe,
I know the difference between a 38 cm and a 42 cm very clearly..... and, MC did not ask about anything
smaller than a 42 cm.
My guess would be that if she figures out "sailing a shortboard"/ gains some control on the Futura 133 with a 42 cm fin, her husband will find a way to get her onto smaller board (Futura 122/111/101) with a 32-38 cm fin.
Under finning her board with a 38 cm or smaller might give her more control, but also that small a fin on a board the tail width of the Futura 133 could induce a whole different set of control issues.

11th June 2011, 03:16 AM
hey roger, you bring out an interesting aspect - namely underfinning a board

my board is wider in width and tail than the SB Fu 133 and runs well with the 40 cm fin

one usually says the max fin length to use is the ofo width
how does one determine the minimum fin length ??
and what happens if one goes under ??

thanx - as always!!!

11th June 2011, 10:21 AM
Hi Joe,
You are underfinned if when you reach top speed and "push" laterally across the top of the fin it lets
go and spins out.
My personal "rule of thumb" for fin length is the fin has to be greater than 1/2 the board width or OFO
The wider the board and the greater the footstrap off set, the more the 1/2 board width applies.
On a Futura or other freeride board with inboard and outboard footstrap positions, you can generally
run a smaller fin (perhaps < 1/2 the OFO width) with the footstraps in the closer to centered positions.
The smaller fin (or underfinned) also depends alot on sail size and overall board speed.
I have really tiny (<25 cm) speed fins that are great if you can head off wind and get them up to > 25 knots board speed.
At 30 knots + board speed they are solid as a rock, but if you have conditions where you can't get them up to speed, you can push them loose any time you like if your speed is < what it takes for these tiny fins to "hook up" and stay hooked up.
Hope this helps,

11th June 2011, 07:00 PM

then, if fu 133 is 76.5 cm wide then a 76.5/2 = 38 cm fin should be the limit ??
i anticipated spin out as being the control factor with small fins
i have seen an article where tinho dornellas discusses body positioning to overcome that
how valid is that ?

hope others are finding this discussion as interesting as i am :)


11th June 2011, 09:18 PM
Hi Joe,
Yes, 38 would be about the limit, but it's only a "rule of thumb".
Nothing set in concrete.
Stance/body positioning could help,
Flattening a sail could help or hurt (depends on how flat the water is, and how fast your top speed
potential is.
So, lot's of "factors"!
The design of the fin can have a significant effect as well.
The Lessacher Duo (Speed and Weed fins with an assymetrical design) can be run much smaller
due to having a bit more area.
Hope this helps,

2nd July 2011, 03:26 PM
Sorry, I would answer, why so long fins.? 39cm Freeride Duo can give you all it.www.designlessacher.eu

2nd July 2011, 08:05 PM
Hello Wolfgang,
Glad to hear from you.
I did suggest that your duo fins could be run significantly smaller.
I suggested the sizes based on what fins the boards come with from
Starboard, and the fact that some of them need some work to get
them to work well.
Can you send me an email privately?
Thanks for your participation here,