Shrinking kite lines

Shrinking? Yes, shrinking. Kite lines get shorter after usage! It seems contra intuitive, because a lot of people think used lines will get stretched, but in fact they get shorter over time. We found differences between used and unused lines of around 15cm, where the used lines got shorter. It may just be the reason your used kite doesn’t feel the same as when you bought it, especially when you just replaced a part of your lines.

A quick search on internet will show that the statement lines shrink is not new or unknown. The theory behind it quickly gets too technical, but it seems to affect a major part of the kite brands.

Line replacement

We got in touch with shrunken lines when we discovered a 2016 North Quad bar had a damaged line due to rubbing through and against the metal split point (see picture). We thought North had solved its split point issue after the early 2015 mistake. But apparently a year of usage will result in some wear out we didn’t expect. Something to check every now and than if you use a 2016 or 2017 quad bar, but that is not what this article is about. The first thought was of just ordering new front lines, but when we checked the length of the new and old lines they were not the same.

Shrinking 25 cm 

In our case the 22m 2016 North back lines shrunk in one year about 15cm. The front lines about 10cm. It is astonishing, but starts to get a bit more understandable when you realize it is (just) about 1% of the total line length.

Back/power North 2016 lines. Upper one: brand new, lower one: 1 year used
Front/steering North 2016 lines. Upper one: brand new, lower one: 1 year used

We asked North line specialist Aurelien Mierswa about it. His answer confirmed our findings as “all our competitors have shrinking lines“. Without getting to theoretically North came -sort of- up with the cause of the shrinking; “…the line is a woven structure. This woven structure gets loos with the time and use. Water, dirt and sand can get in between the filaments. What happens is that the line gets a bit thicker and this makes the line shrink as well.

Also Liros GmbH, a German line producent, clearly confirms the shrinking of lines; “Dyneema lines have the negative characteristic to shorten. This refers in kiting mainly to the steering lines, as the front lines are permanently under tension …But the steering lines that can shrink up to 20 centimeters”.

north-2016-vs-2017
North 22m 2017 back line (unused, with longer sleeve) vs used 2016 line.

It is being discussed at several forums as well, where we both found sceptical but at the same time a lot of convinced people.

One picture can tell more than a 1000 words; See, next to our pictures, a clear photo from the Australian Seebreeze forum, where shrinking lines are seen from Best, Core and other brands.

Credits: Cbulota user on Seabreeze forum
Shrunken Core lines

Our -bit simplified- explanation; line are pre-stretched and get (a bit) back to it’s pre pre-streched length when used.

Affects

There is no need for panic, but what should you do with this information? Well, if you going to replace a line (or two) you can potentially get a problem. Your new lines will be longer than the one you replace. Most brands will sell their lines by only in pairs, which makes sure there is no problem between left and right in most cases, but significant differences in kite flying is still something to worry about. Adding the fact that back and front lines do not typically shrink the same amount, which means over time the angle of your kite can be affected (shorter back lines means stalling is most likely an affect).

So most important message is to check your lines every now and then. Keep in mind that most brands require an equal line length of all lines when the depower is set to maximum (completely open) and the chickenloop against the power. Solving unequal lines is open for debat. Some say stretch (pull) them to make the shorter one’s longer, others prefer to work with (some) pigtails or extensions. Oh and don’t forget your bridles will probably shrink too!

Total Views: 6495 ,
Facebooktwittermail
Facebooktwitter

11 thoughts on “Shrinking kite lines”

  1. Hi Wayne,
    Most of us do that, but it is not about “having a problem”. It can become an issue when replacing 2 out of 4 lines. The lines of most brands do shrink.
    Which brand do you use?
    Dave

  2. i wash my lines in a deep bucket after each use, i haven’t had any major issues and have run lines for years

  3. Hi! I wanna replace my lines in a North Quad bar 2013 but I’m trying to figure out the front lines length, do you know? The steering lines are 24m, I think the front lines are 20m but I’m not 100% sure. This is the bar https://goo.gl/photos/mmGnPYNQKtQ9ums26 I recently bought a 24m line set as showed in this picture and I need to cut the middle lines. Thanks!

  4. Hi, All
    1) Don’t rig your kite on the beach. I pre-rig at home, and unroll lines right before launching
    2) Don’t leave the lines on the beach for hours
    3) Watch the lines. Don’t let people and dogs step on them
    I use my lines for 50+ sessions until they start fraying, and don’t have this problem. I recently replaced the power lines only, and the fit (to the old steering lines) was exact.

  5. All kite companies are dealing with this none stop ongoing issue but they don’t get one thing that there always will be stretch or shrinking if the line have different tensions in the life of the bar.
    A simple solution to this problem is to use same 400kg load line both in steering and front lines. Furthermore lines must be same exact length SO that after 10 sessions user can rotate the lines and apply same load force now on steering lines. You really don’t have to be a rocket scientist to understand this and make it happen.

  6. Hi Johan, we are getting more curious! Please let us know what you see. Some pictures and details on stretch with measurements etc?!
    Great to see some influence from knowledge from other sports.
    Dave
    We Test Kites

  7. Yes I am serious. If dirt is causing the lines to shrink then it seems sensible to get rid of the dirt. I clean my sailboat ropes in the washing machine once a year, and they become good as new. I cannot see why it would be different with kite lines. I will try and let you know the outcome 😉

  8. Hi Johan,
    Are you serious? Stretching is one thing, but a washing machine? No we wouldn’t do that for sure.
    Dave
    We Test Kites

  9. How about cleaning the lines from dirt and sand in the washing machine and thereafter stretching the lines to equal lenght? Has anyone tried that?

Leave a Reply

Your email address will not be published. Required fields are marked *