Thanks for the tips.
The Core PU is really something: look at this thread from last year, where my previous Core bar had a similar, but worse problem:
The local shop replaced the safety line, but this is not really easy on the Core bar - afterwards, the swivel did not work anymore, and I have not used the bar a lot because of that.
This bar is the Pro version. We have different levels of expertise when it comes to taking apart a bar, and I don't really feel comfortable doing it.
Are there other, better, bars that fit well with Core kites, where you don't have this silly PU cover break constantly?