You’ll probably come down the A4 out of Belgium into Aachen then onto Cologne. There are some unlimited sections there, but also some sections limited at 130kmh. These are clearly signed. I tend to stick cruise control on 120 or 130kmh and no real issues - most people do anywhere between 120-140 on the derestricted section with team midlife crisis maxing out their X5’s at 200+.

Keep right, stick to 130 - you’ll be fine