I just bought my first traction kite a few weeks ago (HQ Beamer IV 3m2), have taken it out a few times and am looking to start trying to fly with a landboard.
I've been noticing a problem with the lines (Dyneema) though: they are very much uneven - the right power line is about 20 cm shorter than the left, and I have to always compensate to keep the kite from turning.
Is this normal for new lines? I saw some video tutorials about equalizing lines, but the difference in length to start out with was not as big as I observe with mine. I have also read the shortening using knots weaken the lines. In which case, is cutting the line better? How should I do this without weakening or fraying the lines?
I would appreciate any advice!

20cm? That's around 8 inches. If the kites new I'm sure the retailer you got it from will take care of you. If not you can always contact HQ. 20cm seems a little much for the lines to be out though. Are you sure the bridle isn't tangled or anything contributing to the difference? Try taking the line off the kite and the handles,,,,,,stake down one end of your 4 lines and walk them out,,,,,, if there is a small difference you can always make up for any difference in the leaders on your handles. Tie a figure 8 knot in the leaders to adjust for the difference. If they are truely out by 8 inches though I'd get another set. While the kite is disconnected from the lines is a good opportunity to check that the tow point(where you connect your lines) isn't twisted inside the bridle. If you take your lines off when you put your kite away and you don't attatch the tow points to the velcro tab on the kite you are guaranteed to have everything all twisted next time you take it out. Hope that helps

yeah, after you do what is suggested in the above, let me know if they are still that out of whack. Pretty sure we can get it taken care of.

Tying knots in your flying lines will weaken them for sure and it is not recommended. You can however tie knots in your leader lines coming off of your handles or bar.

You can equalize your lines if needed though. If you have an older set of lines that are finished with knots in the loops then those are the easiest to fix. If your lines are the newer style and are finished with stitched ends then those are a bit harder.

Let us know if your lines are tied or sewn and we can give you more input on how to equalize them out.

Tying a couple knots in your leaders is the easiest and quickest way to fix them though.

I have to expect that you bought this kite second hand? If not your dealer should be very willing to make it right. That is a big difference.

You will want to buy a " sleeve kit " and re-sleave the lines to match. Any decent kite store should have them if not dealers on here do.

I've got sleeving kits but yeah, I'd be suspect of such a large difference without something else being out of whack. Definitely follow kteguru's good advice first

Thanks for your advice, everyone! Kteguru, the 20 cm difference is lines only, not attached to bridle as you described. The ends are sewn instead of knotted. I'll take it back to the shop on the weekend and see if I can get that sorted out.