A few months back we had some really strong winds, perfect to dust off my Isonic 80 and 5.4m Rs racing sail. I fitted my 26cm Tectonics Fury fin and made the 3 mile trek upwind to the old naval base where Artemis racing is setup now. It is a good spot for flat water as the land is pretty low and acts as a breakwater. A couple of the guys from the team were out on their gear also.
When I got there I did a few test runs and found the fastest sections for me were outside the sheltered area and out in the open water. It was pretty hairy so using my North XT added a few clicks of downhaul. I got a pretty good run in and got 33ish knots, then added a click 33ish again, added another click or two and then got up to 34.6 knots peak. The board was really flying so figuring being on a good thing added another click or two of downhaul would be faster.
I then did maybe another 4 - 5 runs but the peak speed never got over the 34.6 knots and it felt like I had more control, but less flightiness. I didn't think about it till later, but is there a sweet spot for downhaul settings where sometimes not using close to max is the fastest option? The sail wasn't over downhauled in terms of feeling twitchy or the like, but perhaps if it was slightly larger like a 5.8m sail it would need to get downhauled closer to it's maximum?
I made a video of the session, can see the GPS tracks at the end. I did my best to go as deep as possible, sometimes when I did the fin felt slightly loose side to side. I use the boom at it's lower setting on the sail, the cutout in the sail seems to be very high for shorter persons. I think the UJ was in the middle position on the board.
When I see some of the speeds others get on the forum, felt slightly disappointed with the numbers considering the windspeed. That said I'm on the lighter side of the spectrum at 160lbs or so and 5'7" and the water was very rough and I haven't spent lots of time to dial in gear and fine tune settings and technique. If there are things that are obvious from the vid would be good to get input.
cheers....
Every sail has a sweetspot....for the wind encountered, first of all, then the rider weight, then the board and sea state.
Just adding more of anything without the necessary compensation will slow your speeds. In your case, without adding more wind, more downhaul might make the sail LESS powered than before, for your size, for your skill and for your preferences in feel for top speed.
If you're moderately powered, often time it's faster using less down and out to give more power for your sail in that kind of wind for your body weight.
Select to expand quoteJohn340 said..
Scotty, Are you planning to take advantage of Hurricane Nicole?
ha ha you know about that eh? Will see was 3.5m weather today but had to work, tomorrow will busy at work powering down the facilities. After that there is likely to be 2 days of 0.5m weather so just hoping for no serious damage. Expecting to be Cat 3 directly over island so not fun unfortunately!
Calling for 65 - 85 gusting to 110 knots!
That speed is pretty good considering the equipment and conditions.
Nothing to complain about.
Adding more downhaul won't make much difference when sailing broad. In fact it's going to flatten the sail and make it less powerful. Power and efficiency is key when sailing broad but a flatter sail is not necessarily more efficient.
How strong was the wind? Unless it was 30knots plus adding more downhaul wouldn't help sailing broad.
Also, next time try a smaller fin, like a Lockwood symmetrical speed. That should add one-two knots straight away.
My best runs in open water chop on my 90lt slalom board are around 37-38 knots - but using a KA23 symmy or Lockwood 21 symmy fin and a 5.8 KA Koncept.
Another thing to try is don't go too broad in large chop. Try a lesser angle of around 120 degrees to slice in between chop. 135 degrees and you are bouncing over chop more. There's no hard and fast rule - all conditions require adjustments.
Cheers Adriano,
For sure it was never something I had considered, the fastest run the board was bit flighty and tad out of control. That extra bit of downhaul gave more control but just felt too easy and the board more planted. I'll have to look up the Lockwood fins, I was quite surprised when I used the small 26cm Fury as I didn't think I'd make the 3 mile upwind trek so easily, but guess when powered up it's not such a problem. I'll have to see what size fins guys are using here.
The wind was for sure in the 25 - 35 knot range, never felt stupidly overpowered, but perhaps at the 80 - 90% of max? There would be times when it very powered. Because I've read people saying go as deep as possible, I basically went very deep, occasionally having to come up to pick a new line through the bigger stuff then bear off on a new path.
I have an old early 90's custom slalom board which is the same dimensions as the largest of the SB speed boards, but for sure narrower and with thinner tail than the Isonic 80 so thinking to repair and see what she might do as a speed board. The rails at the back are for sure less tucked and figure could remove 6 inches of the nose!
I always thought this video by Peter Biji was good in explaining some of the tuning thinking.
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John340 said..Stuthepirate said..
Good luck Bud.
Stay Safe
Ditto
Cheers guys! All that ocean and she decides to pay us a visit!
Will be adding additional straps top the motorcycle and longboard shed! At the moment the eye is going to pass to the west of us, hopefully the further the better. It's the damn tornados around the eye that wreak havoc, 10 years ago one ripped off my bedroom wall! The homes are build of stone, but when the winds are peaking everything just shakes!
Fingers crossed on this one!
Survived without too much damage, this storm though a Cat 3 felt softer going by the seat of the pants pucker factor! 
Just when the winds were getting to the insane house shaking level the eye passed. All in all not too much damage, though I had no power for 3 days so was in camping mode, drinking up all the beers before they got too warm and barbequing off all the defrosting sausages in the freezer.
The 28ft sailboat I race on ended up on the rocks, so hoping she's not too banged up. Also lost the family avocado tree so in mourning of sorts. Heard we can graft the young plants surrounding with the parent, so hoping can rescue in the long run. At the moment eating avocados for breakfast lunch and dinner!!
Yesterday I went out with a 7m sail most others were using 6.2s I thought I would use my 7 as the wind was very broad on the speed run so some extra power might be good the wind was around 20kts and increasing so I gave my sail a bit more down haul it felt really good in the strong wind but it was lacking power so I think I gave it too much as it felt under powered.
I agree, you can use too much downhaul. We've just had 2 days of 25+Kt NE wind. I used my KARace 6.3 on both days. On the second day I eased the downhaul (by 10mm) from my usual position. The crease in the 4th panel was just reaching the dot, rather than the middle of the "a" on the KA logo. The sail had more shape below the boom, felt less twitchy, had more drive and I was 4 kts faster than my peak on the day before.
Of course, the most power you can handle is the fastest setting for sail power.
Winds drop, either a big sail, or less downhaul.
Winds rise, either a smaller sail or more downhaul.
All you're doing is varying the amount of sail power at your disposal. The most you can handle, the fastest you can go. Too much is slow, too little is slow.
