Check also if there is "hard refusion" of that unpaved road ( routing there at no circumstances ), or if there is only very high penalty.
In the latter case,BRouter would prefer even quite crazy detour if possible. If you disable such options by nogo points, it would accept the unpaved road as a last resort.
I remember similar case for a Canadian car driver, as many Canadian roads are unpaved and the original car profiles have very high penalties for unpaved roads.
It was fixed for his case by lowering penalty ( for car-like profiles by increasing the max speed value ).
BTW, I have told Arndt multiple times the car profiles penalizes unpaved roads too much, what makes them unusable for regions with many unpaved roads.
I remember creating an experimental motorbike profile, preferring more winding roads by negative turning penalty.
As I see multiple motorcycle related posts in BRouter mailgroup or Locus forum, I think they would deserve a dedicated profile author among motorbikers. ;-)
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