[quote=SpunMonkey post_id=1107158 time=1597109482 user_id=85813]
[quote=kiteexpertyexpert post_id=1096793 time=1589318373 user_id=100251]
The number one way to tune any foil kite is adjust Z
[/quote]
Any tips for knowing when to shorten z and when to lengthen it?
Im looking specifically to stop wing tip tucking when going downwind. this kite has flown reasonably well and only recently started doing this downwind.
Thanks.
[/quote]
I had this exact problem on my 13m Flysurfer Sonic 2. At first, the tips would never inflate on launch wreaking panic on the beach as I try to steer with only the center foot and a half (tongue in cheek) inflated. I did a long mixer test (see below) which showed my Z was way short. So I lengthened it about 5 cm, 50 mm! which got it to fly nicely except downwind. Downwind, the tips would deflate once in a while and wouldn't reinflate unless stopped in the water and yanking the steering lines. I lengthened Z another 10 mm or so and now she flies great.
As for the long mixer test (LMT), they don't make it easy on the Sonic 2. You have to get the line plan and do some addition and comparison.
1) Add a1 + A1 + AI = a
2) Add b1 + B1 + BI = b
3) Add c1 + C1 + CI = c
4) Add br1 + BR1 + BRI = br
5) Find the differences between a and b, c, br. (a-b, a-c, a-br) and write those 3 numbers on a paper to compare to your kite.
6) Fix the bar side of the mixer (Back-Main and Front-Main lines) to a single point.
7) At the kite, pull with 5 kg of force (I used a luggage scale for accuracy) on the a1 and b1 points and compare to your notes.
8) Do the same for a1 and c1, then a1 and br1.
9) After the LMT, you can now adjust the mixer in this order: C pulley line, B pulley line, then Br line (that figure 8 knot is a b#&tch to loosen).
Or just skip all that crap and experiment with the Z line length to see if that fixes your problem.