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Hank
9th July 2007, 06:05 PM
Hi there.

I currently run on an isonic 87, very nice board indeed. My weight is 78 kg's and my current quiver is Severne CR 6.7 and 5.6, works very nice.

The recommended sail range for the 87 is 5-7 sq m, but as this is my only board I'd like to push it to the limit, and a bit beyond as this is my only board so far.

When hitting 26-27 knots I find that I'm reaching my limit with the 5.6 CR, it's possible to sail, but it's not really comfortable. So I'm looking at getting a smaller sail in order to extend my range.

I would like to stick with race sails (CR type) as I like the feeling of that type of sail.

Question is, would the 5.1 do the job, or is the gap too small ? What are your experiences ?

Screamer
10th July 2007, 09:18 AM
Hi Hank
I haven't sailed iS87, but I can offer you my experience wrt to sail carrying range. I was in situations when I wanted to extend a board's range to the max, and beyond (as you say). I believe that there is a limit to which you can push this, and after that you don't really gain anything. Example: iS122 quoted range is 6.0 - 9.5 sails. My findings (and other sailors' too) are that I would never use it below 7.0/7.3 or above 9.0, unless I was very heavy, very light, or for easy freeriding (not powered slalom blasting).
On top of this, I don't think that going to a 5.1 would be justified (about 9% to your next sail). Above 27 knots (force 7), the water state will play a significant role.

Screamer
10th July 2007, 09:18 AM
Hi Hank
I haven't sailed iS87, but I can offer you my experience wrt to sail carrying range. I was in situations when I wanted to extend a board's range to the max, and beyond (as you say). I believe that there is a limit to which you can push this, and after that you don't really gain anything. Example: iS122 quoted range is 6.0 - 9.5 sails. My findings (and other sailors' too) are that I would never use it below 7.0/7.3 or above 9.0, unless I was very heavy, very light, or for easy freeriding (not powered slalom blasting).
On top of this, I don't think that going to a 5.1 would be justified (about 9% to your next sail). Above 27 knots (force 7), the water state will play a significant role.

LK
10th July 2007, 03:01 PM
Hi Hank

5,6 Severne CR shold be fine in 26-27 kn. Do you have the right mast and trim(downhaul, cam and batten tension) ? I use 6,1 CR in 25-30 kn (95 kg)

geo
10th July 2007, 03:28 PM
Hi,

I second Screamer's view. It's mainly the water surface state relative to board and fin that puts a limit in higher winds; not the sail usually, as modern race sails can really take a lot. And at 78 you are relatively light, but not that much light after all.
If I was in your shoes, I'd rather try with smaller fins. 26-28, depending on construction, would tame the ride quite a bit and let you use your 5.6 more easily. Personally I (84 kg) find a Deb SL2 32 is just perfect on my S95 and 6.3, unless the water is very rough, then it's 30; so I guess you can go down one size for the sail size, and another one for the body weight.

Hank
10th July 2007, 09:22 PM
Thanks for the feedback and good suggestions.

I'm aware of the water role, there's a significant chop, but I don't feel that the board is uncontrollable or unpleasant, it behaves relatively calm. Was using it with a 32 Techtonic Goldwing, better performance than the stock, and the suggestion on choosing a fin between 30 and 28 seems wise.

Sail trim was quite "hard" extra 2 cm downhaul and full outhaul. Rig felt beyond limit, was controllable, but not enjoyable in the strong gusts.


Going from 5.6 to 5.1 is not enough ? What about going from 5.6 to 4.6 or even a no cam sail of 4.8 ? Suggestions and/or experiences ?

Screamer
10th July 2007, 11:56 PM
Hank
Please don't be swayed by my comment re. sail quiver gap, since I haven't sailed neither the board nor sail in question. Maybe it'll work for you, but be sure to try smaller fin initially. Some people reported using iSonics with no-cam Huckers.
My opinion is that for recreational use, these gaps (less than 10%) are not very practical/economical.

Hank
11th July 2007, 12:32 AM
Thanks, I understand, will test with smaller fins first.

I agree with your opinion about the small gap, that's also why I was loooking for input from others, like, does a .5 gap difference really extend the upper level enough ?

There was once a rule of thumb about app 15%, now that would mean that I should be looking at something in the 4.8 range. But was just thinking, and maybe even hoping, that it could be pushed to an extent where the 5.1 could do the job.

Phill104
11th July 2007, 01:06 AM
Hank,

I've sailed my iS87 with a 4.5 and a 26cm fin and the combo felt fine (I'm 85kg). Is wasn't so much the board sail combot that was a problem that day but the big messed up chop we had on the lake. I think on a flat venue such as West Kirby or The Ray (speedstrips in the UK) that it would work well down to this size for my weight.

There does come a point where a smaller board is really needed though but I think that is more down to an individuals preference, ability and chosen location when we are talking pushing a boards range by such a small amount.

Hank
11th July 2007, 02:23 AM
Phil, sounds great that the board behaves ok despite being pushed beyond its "recomendations".

As for the sail gap, do you - and others, agree upon that the difference from going from 5.6 to 5.1 is too small ?

What sizes does your sail quiver have in the smaller sizes ? Type and/or brand of sail ?

Phill104
11th July 2007, 02:32 AM
I have all Tushingham sails. These are well known for their wide wind range but in the smaller sizes I find .5 about right. It's true that I could hang onto my 5.7 well into the wind that I would use the 5.2 with but it's often better to be comfortable in choppy conditions with at least the sail. It give me more time to think about the next bit of chop.

My current quiver is a bit messed up but here goes.

8.5 Lightning, 7.8 Lightning, 6.5 Tbird, 6.4 X-15, 5.8 X-15, 5.7 Storm, 5.2 Storm (soon I will add a 5.2 X-15), 4.7 storm and a 4.5 Storm (soon to be replaced with a 4.2)

The Lightnings are 2 cam, The Tbird is a rotational freeride sail, The X-15s are 5 cam speed sails and the storms are high wind freeride/wave sails so you can see why I have so many sails of similar sizes.

Hank
11th July 2007, 03:08 AM
Wow that's a lot of sails ! But ok you got a couple of different board types as well.

I have the same thoughts about choosing a smaller sail, it's purely for getting the comfortable ride and being able to control it better in the higher winds.

Besides the difference in handling and feeling, do you think that the max limit of your no cam sails is identical to that of your cam sails ?

Also, when you change from your 5.7 to the 5.2, how much app does it add knots wise ?

Thanks for all the input, much appreciated.

Phill104
11th July 2007, 05:20 AM
Thebiggest problem I have is that I often sail on an inland lake. The makes for very gusty conditions requiring the need for a bigger sail. Often in winds where I would be on a 4.7 at the coast I will need a 5.7 on the lake. I never really look at the windspeed as I just rig up on feel for the conditions. Here un the UK, summer winds can be blowing the same speed ad winter winds but have far less energy in them also requiring a bigger sail for a given strength.

The cammed sails take about the same amount of wind (possibly slightly more) as the no cam sails but remain stable. When reaching overpowered on the no cam sails they begin to get twitchy but the X-15s just stay as steady as a rock. This allows me to just keep accelerating on the iSonics until my bottle goes. Their bottom end is not so good though (suprising considering the amount of pre set shape) and really like to have some power in them.

What I do notice is that you need to carefully select your sail from a range. One 5m from one brand can feel and behave more like a 4.5 from another. If you play it right the .5 difference you wish can feel a lot more by careful sail choice.

I'm sure others on here can tell you a lot more about this than me though.

adaminkernow
12th July 2007, 07:38 PM
I wouldn't really want to use too small a sail on that Isonic. 6-6.5m is pretty much optimum in decent powered conditions. You could use a 5m but this would feel a little small for an 87 board. I've used the 87 with 6m and this combination felt ideal. With my other slalom board (Falcon 90). The X15 5.2 was a little small and did not feel great, although useable.
6m should be great with plenty of downhaul and a small fin in winds upto 30 knots, provided it's not too rough, after that I would certainly be looking for a smaller board if not before.

ThierryP
12th July 2007, 09:15 PM
Hi Hank,

I am the same weight like you, and I have a Sonic 85 (2006) that I use with 5.9 and 5.5 race sails (first with MauiSails TR-1s, now with TR-3s) and a Tectonics Goldwing 28 cm. I agree with some of the posts above: at 26-27 knots, you should still feel very comfortable with a 5.6. So definitely use a smaller fin before buying a smaller board. If you like your Goldwing, go for a 28 cm, it works beautifully with the board. I think that you may not need a smaller sail once you use a 28 cm.
However in case this was not sufficient: I disagree with some of the replies concerning the gap; a 0.5 sqm gap is definitely not too small between 5.6 and 5.1, you will feel a very significant difference. While it is true that you would be better off using a smaller board than the iSonic 87 with a 5.1 m sail, I think that it is still OK (but I have not used that combo before, because I always use smaller boards with a 5m sail).
Good luck!
Thierry

geo
13th July 2007, 01:53 PM
Hank,

reading one previous post I saw that "... Sail trim was quite "hard" extra 2 cm downhaul and full outhaul. Rig felt beyond limit...". Just thinking: what do you mean by "full outhaul"? Did you make the sail totally flat, so that rig dynamics were killed? Maybe your problems actually have same root there (it seems strange to me that a 5.6 race sail can't take just anything at 78 kg.); a totally flat sail will behave wildly, giving no power and then plenty top end once accellerated. Probably you were slowing down on every chop and having to accellerate again each time. Maybe?

Hank
13th July 2007, 02:28 PM
Thanks for all the feedback from everyone.

I've ordered 2 smaller fins, 28 and 30, and will test that before heading out for smaller sail or perhaps even a smaller board, which as of now has the lowest priority.

About the sail trim, I did write totally flat, but by this I meant as far as possible and still having curve and an ok set up sail.

Thanks again to everyone.