Flat sails

are you using the correct masts ?
most race sails are very mast specific and will rig like a dog if on the wrong one.

+1 on ratz said. The first thing you need to do is make sure to use the correct bend of mast.

Many sails work well with "constant curve" masts, but there are a few, such as the Maui Sails TR line, up to TR-9, that require what Phil McGain calls "stiff top" masts. If you rig these with constant curve they don't work well.

All that said, there are some race sails, such as my old Sailworks NX4, that don't have much bottom end, even with correct masts and correct rigging. They were designed for top end speed.

Masts are really important.....as everyone else has already said.

Tuning as you have said that you don't tune is just as important. If they are full on race sails they are designed to be used fully powered up too and with the right board.

Don't just set the downhaul and leave it, use less twist for lighter winds so less downhaul.

Use less outhaul too for lighter winds. Most of the time when there is a stated outhaul length, depending on the manufacturer, this is their high wind setting and usually for light winds reduce by around 4-05 cm and medium winds by 2-3cm.

Make sure there are no wrinkles coming from the battens and if there are, tension them.

best thing is to rig the sail and then post pictures of it, put what wind strength you would use this setting on ie, high wind etc.
Board pix too are always helpful.

There is an old saying, "The definition of insanity is doing the same thing over and over again and expecting a different result"

There is no magic bullet. There are many variables to having a good set up
- mast / sail compatibility
- downhaul
- outhaul
- batten tension
- boom height
- mast base position
- foot strap position
- board type and size
- fin type and size

Change one thing at a time. Take note of what improves your sailing. Work through the list. Over time you'll figure out what works and what doesn't. Small adjustments can make a big difference.

It's taken me nearly a year to adjust to my Warp / Falcon gear, after using KARace / Mistrals for 5 years.

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Macroscien said..
All my race sails are mildly flat but sails of my sailing companios comes with nice belly.
What I am doing wrong? The obvious problem is that I am not tuning my sails , only adjusting downhoaus or outhoul
I am the last to get planing and the power from my sails is miserable ( although easy to control in strong wind)
I try to compensate using bigger sails for the conditions , but I suspect the sometimes the smaller is better...
Should I do something with battens ?spacers on cams ? How do you know if battens are setup properly ?How extending may effect ability of cams to flip?

any tips please

I use Severne and NP race ails

I learn't to tune sails by having adjustable controls on the water... outhaul, downhaul and harness lines being the three main ones. Racing with one sail in varied conditions on different points of sail teaches you how to get your best from that sail at that moment. I will even adjust all three settings when changing from upwind to downwind.

I don't normally run an adjustable downhaul on a slalom or freeride sail but it may be worth doing it for a while so you can make easy adjustments on the water. We all get lazy and coming ashore, detaching the rig and fluffing around with down haul mutlipe times in a session if often just to hard so we put up with what we rigged. If you leave it to next session to make adjustments then the conditions are different and you may not notice the immediate change as much.

Select to expand quote

Macroscien said..
All my race sails are mildly flat but sails of my sailing companios comes with nice belly.
What I am doing wrong? The obvious problem is that I am not tuning my sails , only adjusting downhoaus or outhoul
I am the last to get planing and the power from my sails is miserable ( although easy to control in strong wind)
I try to compensate using bigger sails for the conditions , but I suspect the sometimes the smaller is better...
Should I do something with battens ?spacers on cams ? How do you know if battens are setup properly ?How extending may effect ability of cams to flip?

any tips please

I use Severne and NP race ails

Same here, all the guys I sail with have a belly...

Assuming the correct mast and assuming we are talking about cammed sails or camless slalom/freerace sails:
80% of sails I see rigged too flat is due to far too much outhaul (from not experimenting with tuning)
The other 20% is due to too much downhaul.