Hmmmm.... I could be wrong but that looks a lot like a 2007 Koncept to me, not a 2008.
In my experience using Koncepts in very well powered up conditions I have found that more down haul past a certain point is definitely NOT always better. There is a point where that sails actually get 'twichy' if you overdo it, especially if you use a lot of outhaul as well.
The 2007 works best with moderate downhaul and from almost no outhaul to a few cm of outhaul on the KA SDM masts. I have never run that model on the RDM so I can't comment, it has always worked so well on the SDM that I never felt the need. The 2008 5m Koncept works well on the KA RDM but being a bit flatter in its cut down low it is extra important not to over trim it. Use just enough downhaul to get the top leech loose about halfway to the boom and as little outhaul as you can consistent with eliminating back hand pressure. If you overdo it you may well make the sail feel twitchy.
Check out the rigging guides on the KA website. They are on the home page. Just keep scrolling down until you find them.
Here is the link to the 2007 guide: http://www.kasail.com/windsurfing/sails/2007/koncept_rigging_07.html
and the 2008 guide:
www.kasail.com/windsurfing/sails/2008/ka%20_koncept_2008_rigging_guide.pdf
Hope these help.
Cheers, Andrew Daff
thanks for the tip andrew, i have checked out the rigging guide you posted on the KA site, and your rite the sail doesn't like a lot of downhaul or outhaul, that's why it is such a powerfull sail for a 5/0, if i use it in those conditions ill be happy, but after saying that in my oppion its the mast, the sail could have a bit more shape at the 5th batten(or is that the way its supposed to rig) so ill see if i can borrow a sdm400(could be a bit stiffer) and see how it sets. thanks for your help
Sorry to say it keef but I do think you are on the wrong track. Chris Lockwood has done a lot of tuning and testing in all conditions and we have found pulling shape out through that batten 3 area and stabilising it with a modified batten has been a big improvement in feel, speed and stability. I have not noticed one bit of negative difference from a gybing perspective. Other sailmakers have been progressing in the same direction.
To get back to original question about gybing:
I don't understand the meaning of the statement below. (spelling corrected )
Quote: "....the 2nd setting is download it to what Mark recommends and you have a speed sail that is unbelievably light and powerful in strong winds (with the draught set forward ) but is very unforgiving in the jibe (not enough backhand pressure).
What I don't understand is why anyone would actually want more backhand pressure in a sail that is 'unbelievably light and powerful in strong winds'.
I hate to have to say it but this sounds like more of an issue with Gybing technique. Do you have some photos, or better still videos, of yourself gybing keef? There are plenty here (including myself) who are only too happy to analyse gybes and help with tips.
this is the only pic i have it was taken a few years ago, and im happy for any negative comments, well thats the only way to learn, as you said andrew KA have the best guys testing and developeing sails and i want to change them but i still think that the leach on the 5th batten is to loose and that could be the problem. and the problem is mainly when the sail is to tight don't get me wrong i like the sail it's light and powerfull, i just did the post to see if anyone had the same problem and obviously nobody has it's only me
, and maybe your rite it could be my technique
Hi Keef, You really do not want much shape in the top of the sail. A lot of shape in the top of a slalom/speed windsurfing sail makes them very heavy and physical to use and reduces the "top end" range and speed.
It is simply a matter of leverage . As the boom is connected low on the mast the sailor does not have a huge mechanical advantage over the rig . Focusing alot of 'pull" in the top of the sail makes it very difficult to counter balance.
If you focus the majority of the power in the lower half of the sail, the power is easily controlled by the rider and the sail has a much lighter feel and more range.
There are some exceptions to this . Long board race sails for example which are aimed at max power in the low wind range . These sails however have reduced 'top end', there is always a trade off.
The Koncept is a speed/slalom sail. The focus is on controlable power and top end speed and it is highly successful at delivering this, but like any sail it cannot be all things for all conditions.
i hear what your saying martin ill be giveing the 5.0 another go today(n/e 25knts allready at 12.pm) and i am in the market for a new sail something like a pride rs 7.8 so ill be giveing the koncepts some consideration
Hey keef, that gybe entry looks really good. It's the next part that is always the tricky bit but you are set up well there.
The next steps are to:
- slide the front hand up to the front of the boom
- let go with the back hand while still carving
- give the boom a little push to your left so the sail simply pivots
- reach under and grab the other side of the boom with the new front hand
- switch your feet now by taking your old front foot out of the strap and putting it in the middle of the board between the front and back straps and either slipping the other foot into the new front strap OR putting it on the deck next to the other foot so you can put the other foot into the back strap first.
- plane away with a smile!
see here:
Hey Keef,
Just my 2c from having had a bit to do with testing, development and competing on those sails...
Problems gybing your 5.0m could be too much downhaul and outhaul, or there simply wasnt enough wind where you were choosing to gybe (gusty). The 5.0m sail is small, and will not provide a lot of support unless you have plenty of wind- especially through gybes.
If there are other guys out on 6.0s hanging on comfortably, then the setting you had in the first pic actually looks about right. If you find your body is getting lifted off the board in the gusts, then you need a bit more downhaul. If everything feels balanced on a run, then there is no need to put more downhaul on.
There is a simple balance that needs to be maintained. The centre of effort has to be a certain height for a given stance. If you are sitting very low to the water, you can drop the centre of effort with more downhaul (increasing the twist in the top of the sail). This works up to the point where the shape is sucked from the front of the sail and the profile no longer can handle the large apparent wind angle changes we experience through gybes or in strong (gusty) wind. This works great on flat water for speed conditions (Thats you, Sandy Pt/Vic crew). But in chop we have a more upright stance so the centre of effort needs to be higher.
So with smaller sails, the mast is shorter, so to keep a similar stance and balance you need more shape and less twist at the top of the sail. If you rig a 5.0 to look like a comfortable 6.6m it will feel like crap unless you are sailing in a gale in dead flat water with your bum just about skimming. Some of us get to sail in that (normal day at Sandy Pt), but the rest of the time you will be better off with less downhaul on the smaller sails. Dont listen to the crap from guys saying it needs more downhaul based on what larger race sails look like. It does not apply with 5.0 or smaller.
The reason sub 5.0m wave sails feel quite comfy in 20-30kts is that they dont have a lot of twist, nor shape (camber) down low, so the COE stays at the correct height for balance. You can add some downhaul (=>more twist) to them without sending the COE too low, since the bottom of the sail is relatively flat. This will just depower the sail without significantly lowering the COE. Race sails are a different beast with all that camber down low.
Just thought I'd add, the new ('09) production Koncepts are a significant step up from the past few seasons with much better quality finish, and "out of the bag" performance. Very impressed. Cant wait to try the smaller ones (but might be asking a bit much!)
PS: I just got a new CA SL55- its a weapon... great topend and insane around the corners.
thanks slowboat for takeing your time and the advise, the reason i did this post is because all of my sails are prides rs&rss and they have wider booms and need more downhaul than the KA'S, i rigged the ka yesterday in a 20to25nt n/easter with hardly any downhaul ,thats no crank(to the extent that the bottom batten wasnt popping when gybeing) like a bit looser than the first pic, so i gave it a touch more and that sorted the batten out and it was a different sail, as you said fully powered up great to gybe, less wind and it's a bit twitchy
i'm in the market for a new 7.8 or around that mark and if the bigger sails have the same light feel and power the 5.0 has id would be have a look at them, unfortuneatly there's no demos down this way
allso thanks for the tips on rigging
i was talking to james about last july and he said he was in maui testing the new 55's and said he was sticking some cutouts on them ,wether he did or didnt he was really impressed with the changes, i love my 55 and i don't think you can talk me into these wide tailed low volume boards
keef, I just tried my new 7.5m today and its _nice_. Rigs cleaner than previous years and the rotation is fantastic. Very happy so far. Cant wait to try the smaller ones.
The new CA slalom boards dont have cutouts. They dont need them. The tails arent super wide so you can run a shorter fin. I really like these longer slalom boards with narrower tails. Way more comfy in rough water- no stressing about burying the nose, and you can do nice long drawn-out carves rather than just the short snappy hub-cap turns of the wider tail boards.