Learning to fine-tune slalom racing sails for speed windsurfing requires experience, patience, and experimentation.
In speed record challenges, all small changes in the sail setup have deep impacts on performance.
Dutch riders at Ghosts of Speed have tips for you.
Downhaul
Downhaul is very important. Use the recommended settings with less than half a centimeter on a few occasions.
Test it to see how far you need to downhaul your sail to get enough leech twist.
Don't use too much outhaul.
Try to make the sail touch the boom to the rear harness line to open the sail properly.
With an adjustable outhaul, get the sail flat for upwind runs to save you energy and, in downwind runs, release the sail into a more loosened profile.
Boom, Mast, and Harness
Boom height is also relevant.
In strong wind conditions, use the boom in a low position for maximum control.
Keep your boom rope tight to the sail to get much more speed.
The top head of the sail should be positioned in the right direction. Otherwise, the sail won't open for speed windsurfing.
Distribute your mast hand to hold 40 percent of the power and your sail hand to get 60 percent of the energy.
The idea is that when you're turning downwind, the sail starts to react to the wind and opens a little bit.
In low-to-moderate winds, get your harness lines short. Set your lines back in overpowered wind conditions.
Put your mast track more to the front to keep the windsurf board lower, but if you lose fin pressure, get the mast to the back again.
If the nose of your board gets up, you'll have to lower your boom.
With wind gusts, the sail needs to breathe through the front to keep speed and maintain control.
Battens
Make sure your lower battens are really tight, with a nice full profile. Don't put too much pressure on the third batten.
Get enough pressure on your cambers.
There should be enough pressure on the lower cambers so it doesn't deform in the upwind course.
Inserting spacers in the cambers will increase camber pressure.
The Ghosts of Speed are Jurjen van der Noord, Peter de Wit, Hans Kreisel, Dirk Jan Knol, Martin van Meurs, Luc Salomons and Barry van Lingen.
Words by Luís MP | Founder of SurferToday.com