4 minutes ago, Insorior said:
Regarding 2- I realized afterwards that my alphacool tubing is ID13mm OD16mm while the insert is only 12mm. It had some room inside the tube. May the bending come from this ? Should I own a 13mm insert instead ?
What are the other causes of tubes collapsing / pinching ? Mabe was it not hot enough ?
This is the problem, yes, you need a proper 13mm insert otherwise there isn't really anything you can do to stop the tube from collapsing a bit.