The detour through the industrial area is only at “curvy route” and not “fast and curvy route” selection. Even more: on the crossing back to the B8 a left turn is forbidden (Google Street View).
I have tried to use this “feature” to block this routing by adding restriction=no_left_turn, however this doesn’t seem to work (I am far away from having skills in OSM mapping, so probably I used the tag in a wrong way).
Is an OSM expert around who could check and help me fixing this routing issue?
Adding turn restrictions is a bit more tricky. I added the turn restriction.
If you want to add this on the OSM website, try to click on the node (dot) between two roads. Then you will see an image on the left side, where you can change the turn restrictions.
Yes, stupid me. I have added the tag to the entire street, but not to the specific crossing… Makes much more sense: how should OSM knows on which end of the street the left turn is forbidden.
I will check in some days if this helps to prevent the detour.