Front line stretch after less than three hours use

[SpunMonkey]

Used a brand new Ozone race bar last weekend with standard(non race) 25m lines. After a quick 30-45 mins on a Chrono 12 Saturday and then about 3 hours on a 15m chrono the next day I checked my lines. Five inches of stretch! Had to add sidline pigtails to each sidline to account for front line stretch.

Is this normal?

[revhed]

Yes normal if not pre stretched at factory, and even still.
This is called "creep" as the spectra fibers that are woven pull thinner and therfore longer.
Interesting to note that humidity, temperature and most important getting lines fully wet and then loading them a lot will change the length.
We normally prestretch ALL our lines before flying for the first time.
Attach to a solid point and really lean into them pulling slowly, one at a time, even this will not get all the creep out, only flying will.
I check mine often but most break in well after a while, different lines will also react different.
R H

[SpunMonkey]

Thanks Revhed. Happy to know that is normal. I made the mistake thinking that lines would be prestrectched for use on a kitebar. Certainly pays to check the lines regularly!

[dyyylan]

Many brands pre-stretch but many do not, cabrinha and best are kind of notorious for having super stretchy lines

[BWD]

From memory I think stretching to 60% or so of rating is recommended.
I have used the pulleys from old windsurf gear to properly prestretch lines.
4:1 to 6:1 allows a good 250-300kg pull. Don't overdo it.
Not sure just hanging on the bar is enough to avoid having more stretch happen from riding.

[Slyde]

I'd be pretty sure you have been given a bar with the standard rear leaders rather than the race bar rear leaders. There is a difference of about 6-10cm from memory. You should not experience that sort of stretch after a few sessions. If you have a non race bar check and see if they are the same length as standard or not. If not take it back and get race rear leaders.