I'm going to start using larger sails on my boards to extend their wind range. Is there any fin guide 'rule ' around..
I usually dont go bigger than a 5m on my 95 rocket but I will now use a 5.8m + 6.6m cammed. On my 125 rocket ( 69cm wide) I currently use a 30cms for the 5m & a 38/ 44cm for the 6.6m..so do I keep the same or what?
The 95 rocket is 59cms wide.
I also want to try & get the 78ltre pocket wave more usable.
I usually only use a 4.2m (24cms fin) 3.8m + 3.2m( prob 22cm or 18 if a weedy).
Whats the biggest fin I can use on it? I'll probably need to buy a bigger one as it's US box so I can't use any of the bigger ones I have.
That 44cm fin on your 69 wide with a 6.6 is already on the large side. You could easily go to a 7.8 or similar without having to get a bigger fin.
24 about the largest for the wave board, but it is interesting you use that with 4.2. 24 on that board would be for 5.5 - 6.0 and the 22cm be a more alround fin (in wave use_ .................but as you are B&J ing on it you could pretty much use whatever. I'd say 20 for your smallest sail and really blowing and 22 for the 4.2
sorry to hijack ur post 
Im also looking to get another fin. At the moment i only have a 46cm fin. I want a smaller freeride fin because the large fin is to big once the water gets a little low 
I have the same board as sue (125l rocket, 69 wide) and my sails sizes are 4.7, 5.2, 5.7.
Thanks
sorry again 
As a rough guide for freeriding boards and sails.
Sail size x 6 ie:
4.4m x 6 = 26.4
6.6m x 6 = 39.6
and so on
I have a link on my other computer to a website that calculates fin and sail sizes for weights and winds.
I'll post it later tonight if someone doesn't beat me to it
[edit] Found it
jimbodouglass.blogspot.com/2010/11/updated-windsurf-calculator-online.html
Another example of the same board/sail/fin calculator here:
www.poolewindsurfing.co.uk/windsurfing-boards-windsurfing-sails-size/
You can also download your own excel spreadsheet version of the above calculator at:
www.poolewindsurfing.co.uk/wp-content/uploads/2010/01/windsurfing-equipment-calculator.xls
To be honest with you Sue and with respect to others opinions, I would suggest emailing Tabou and popping the question to them as I think the board manufacturer would be the best source of this information (luckily the same one for the three you mention!). Make sure you mention what year your boards were built and your weight (and obviously the sail sizes you plan to use on each board).
Re fin sizing for pocket wave, worth considering intended use of board (high wind blasting vs waves) as the manufacturers recommended fin sizes for wave sailing would likely be smaller then what you would use just for blasting about (maybe mention that in the email whether you plan to use it in the waves or not).
I tried my 7.2m NX on the 95 ltre board at the weekend with a 30cms fin. I only did one run and muffed the gybe but I was suprised at how much easier it was in a straight line in the chop.I think I'll be falling in on the gybes for a while with the heavier sail but I'll use the smaller board in less wind now.Just got to learn to uphaul it in slop..
I also used the 5.8m + 30CM fin with it as the wind was picking up and enjoyed sailing into the chop and got some jumps for the first time in ages although the boards was still a bit big & bashed into it on one tack.
As I was tiring I then puton the 4.8m hucker and I musy admit I do enjoy the smaller sails! It was the first time I'd used the Hucker and boy ..it even made my crappy chop hops feel good!
FYI Sue,
Tabou Freeride 34 - $80 @ www.seabreeze.com.au/Classifieds/Windsurfing-Accessories/~bd130/Tabou-Freeride-34.aspx?search=gvyj2BKrnvnVeriJG8S9vDhRRrLKK3Lz
Might be a bit obvious but I generally have a rule for myself (well, more of a guideline than a rule) to use a smaller fin than sail.
So for a 6.6 m2 sail use a fin smaller than 6.6m2. For 4.2 m2 sail use a fin smaller than 4.2m2 and so on.
Generally it is very hard to find a fin anywhere near as big as a sail, so generally it is an easy rule to follow
Glad to be of some help.
yeh i think the problem is that 7.2m sail, its to big & that 125lt board.
i've got about 20-30kgs on you & my big board is 98lt, the biggest sail i like to use is a 6.2. I have a 7m but only use it if i have to <15kts & i normaly go do somthing else if its that light.
I would be using your 95lt as a big board & ya 78 as a little one. My little board is 85lt so it sinks if it not blowing 25 30kts min.
Nah I do that any way..
I wonder how fin size relate when you are coming into overpower conditions ?
Usually you want your fin to get you planing as soon as possible but when over powered I think that smaller fin has advantage.
I have been sailing today from 2 pm to 5:30 on my 8.0 m2 RAM at 22 ktn, 110 L on quite big chop on Shearwater and 34 cm fin was just right top achieve top speed and slight and soft over that chop.
In lighter winds I use 44 cm.
I am not sure if sizing down fin would help if I want to extent to 25 ktn in the same choppy condition on my 8.0 sail.
As today I get relatively mild spin out only once...
I feel like 8.0 for that condition was perfect and I could easy handle up to 25 ktn and be still in control and allow for full speed over that chop.
What the pleasure when you could now pass motor boats stragling on that chop and you could nicely fly over it 
