there are quite a few new members on the forum and something we talk about but probably not enough, line stretch, and how it can/affects performance.

Last week I checked all 3 of my flysurfers, and my Peter Lynn bar. Keep in mind these are depower kites so when I say front lines would be power lines on fixed bridal kites. Rear lines would be the brake lines on FB kites.

All 4 front (power) lines had stretched by as much as 5 inches. A couple sets 3 to 4 inches. What this does is pull on/ make your rear (brake) lines tighter causing the kite to stall and fly slower in the window.

How to fix this is to lengthen/stretch your rear (brake) lines until they are the same length as your front (power) lines. Easy to do, find an anchor point to mount your lines. I use a 3/8" drive, 12 inch wrench extension to feed thru the line loop, and pull like mad. Once all lines are equal length reconnect and your ready to go!

I would recommend doing this every 30 to 50 hours flying time or when performance of your kite starts to drop off.
Hope this is helpful to you in the future.....................

Did my big Cab bar last season ... now it's about a cm out.
Checked my SA2 - it's about 5 inches out :o but it flies so sweet, I don't want to meddle with it

I adjusted for stretch on all my bars in the past couple of weeks. Reset on the SA2 paid off. Perfectly tuned yesterday for a light wind day. I aways kept the trim 80% closed and that ended up the length I needed to shorten the front by. Also the center line was longer by a few cm.

Conversely, since on most depowers the center and rear lines are of the same strength, you could just swap them for a session and let the kite stretch them out for you.

Kamikuza, definitely try it, you can always go back....you'll be missing depower on your throw with long front lines. I imagine having all the usable depower throw on the SA2 19 would be a very good thing! Might even increase you're range on both ends of the spectrum cause FS like sheeting out to get the kite moving in light winds.

Quote:

Originally posted by B-Roc Conversely, since on most depowers the center and rear lines are of the same strength, you could just swap them for a session and let the kite stretch them out for you.

I would not recommend this method...............the rear lines would have too much slack................alot of kites have kook proofs that also have to swapped around..................just easier to stretch and trim correctly................................

I think he's talking about the FSers ...

Which makes me wonder - all the over-sheeting I can apply with the setup as it is at the moment - I wonder if that's why the kite is NOT overflying when I jump ...???

very helpful! can someone explain how to do this for the PL nav bar? My rear lines are not the same length (which I can use this method to fix), but the front lines seem to be slightly uneven and those are not regular lines, I think it has to do with how the V-split is set up. The lines seem to be the same length but since one is tied to the line behind/inside the stopper ball and the other is tied to the loop, the one tied behind the stopper ball ends up being slightly shorter (from the kite's perspective).

try pinging rippsession, carltb, phreerider, flyguy, flyjump, Todd, acampbell, or shehatesmyhobbies....................the all have nav bar experience

here's my general approach to most things

http://vimeo.com/29221581


less than 2 inches no big deal. if more i add a square knot at the sleeve starting at the kite end to make near even terminus. stretched and STABLE is good , if it keeps stretching its over.

check points are ...kite stable in idle at 12 and bar is even. if a front to rear problem, trim will take up the discrepancy. FS are far more sensitive than ARCS in this regard. bar being even and equal turn rate is where to judge need on rear line problems . i think there a leader knot adjust on the bar ends as well.

I stretched the rear lines so they are even (or with less than .25 inch difference, probably around .2 inch or less). Tied the ends to the end of my spreader bar, the other ends to a carabiner to a post. This worked well I think because it let me place the unstretched line about an inch further on the spreader bar than the one that doesnt need to be stretched so I could stretch it "faster", then just take tension out and move one line so they are equal and see the sag. Repeated this until the sag was almost identical, which took about an hour of pulling and bouncing... maybe there is a faster way but placing both lines at the same point while stretching seems like it would take even longer. I did have a pretty big difference to start with though, not sure how much exactly but somewhere between 1 and 2 inch difference.

Phreerider... what do you mean by "if it keeps stretching its all over"?

Just waiting for the wind to test the kite. I was playing around with the pigtails the previous owner had used maybe to solve this problem (two which were about 8-11 inches long and misplaced one so hopefully the trim makes up for it. Im not even sure if they were on the rear or front bridle attachment points anymore....

The rear lines are longer than the front ones though, I think thats how it should be anyways.

with a NEW set of lines stretch to match is a good thing, if not prestretched already. usually a session or 2 will bed the lines do the same ...then you can check for change and adjust a little. i like to knot the stretched line if it is stable rather than stressing the lines to match esp. on an old er set. new lines will tolerate the load, old lines will not. as the polymer ages and has UV exposure it becomes brittle. so fresh stuff you stretch and old you knot.

if you have one line that keeps stretching with unpredictable rebound, it (the fibers within the line)has started to fracture and it will fail under shock load.

and buy old i mean 300hours + and very few make it passed 500hours.

if there" fluffy", esp. at the loop connector, the end is near and stretching will only accelerate it.