[This relation looks close][1] but needs the node where you can't turn back to the other side added as a "via" node - especially in this instance where it looks like the ways join at both ends (can you do a U-turn at the other end - that would need to be a second relation with a different via node and the from and to roles swapped). Edit: if the roadsign says no u turn then that is the restriction type to use. In practice no u turn or no left turn in this instance with the same from and to ways and via node should work the same for routing. [1]: https://www.openstreetmap.org/relation/1650531#map=17/21.54260/-105.27883

[This relation looks close][1] but needs the node where you can't turn back to the other side added as a "via" node - especially in this instance where it looks like the ways join at both ends (can you do a U-turn at the other end - that would need to be a second relation with a different via node and the from and to roles swapped). [1]: https://www.openstreetmap.org/relation/1650531#map=17/21.54260/-105.27883