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docgr
13th September 2009, 10:43 PM
Hi everyone,

I-sonic 111 with a 7.1 Point7 AC0 - 38 Drake fin
I-sonic 86 with a 6.2 NP RS slalom - 32 Drake fin

Tried several times, but every time i approach 30 knots always ... always spin out (29,77 spinout ... 29,50 ... and so) both with te 111 and this morning with good wind and the 86.

Ok, I'm going to buy SL4 fins ... but ... is there something else about the trimming that I can do? .. Seems so strange to get 28 ... 29 ... apparently without problem and then .... ooops the board always start sliding ...

Quite a newbe i speed matters .. of course :)

Thanks for any advice

Giorgio

Remi
14th September 2009, 06:17 AM
Hi Giorgo,

This can come from many things, from you or from your trim, so please let us know this :

Boom height :
Harness line lenght :
Footstraps position :
Mast base position :

All the best

docgr
14th September 2009, 05:38 PM
Hi Remi

(I've posted the same message in the Ask our team ... didn't find a way to cancel this one ... )

Anyway

I-sonic 86

Boom height : with the 6.2 NP rs slalom between 1/2 and 1/3 of the sail hole
Harness line lenght : 26"
Footstraps position : both external ... front holes for the back straps, rear holes for the front strap
Mast base position : 1 cm forward of the center


Thanks!

Giorgio

Remi
16th September 2009, 12:54 PM
Hi Giorgo,

For the footstraps, try all in the back for the back one and in the middle for the front one.
Boom height should be around eyes height and harness line adjustable and need to be more longer.
Fin can be a problem, please sand all your Drake fin with 600 gr until you take off the Drake sign.

Hope this help.

All the best

docgr
17th September 2009, 12:12 AM
Thanks!

Harness line are adjustable (my fault) max is 28" ... enough?

All the best

Giorgio

Remi
17th September 2009, 03:16 PM
Hi Giorgo,

Personally I am over 30, but basicly minimum as long as your under arm.

All the best

Ian Fox
17th September 2009, 05:55 PM
Hi Georgio,

As Remi had commented, this can be many factors, some well outside our visibility or control; one more to consider; outhaul/draft stability in the rig. No, it's not to deflect "blame" from fin etc, but as the speed builds up, the sail loads increase due to apparent wind loads (this can vary a little according to sailing angle, but consider you hold the same line/angle to wind) - under increased load the sail draft tends to move backwards (even in best sails - yes, but better ones move later and less) - to combat that you sheet harder with back hand - to offset backhand pull you (even unknowingly) counter by extra push on your back foot - and there comes your magic 30 kt spinout eachtime.

Typically a lot of guys use a "more powerful" negative (or non positive) outhaul in the attempt to get more power for more speed, which up to a point is correct, but the ideal sail trim for acceleration can often not be ideal for top end.

Very easy to test/try and see if this helps. You might be suprised, it's a common thing.

Cheers ~ Ian

docgr
18th September 2009, 01:34 AM
Interesting Ian
i've used actually a very negative outhaul .... Adjustable while sailing ... Saturday I'll
try a little flat sail .. But i didn't feel too much pression against my back hand

thanks

Giorgio