I´ve noticed that Graphhopper ignores the use_sidepath tag when it´s in combination with the bicyle:forward/bicycle:backward suffix. Is this a bug or a “feature”?
An example would be this route here where the Graph Hopper router prefers a tertiary highway (together with negative class:bicycle values) over a compulsory cycleway next to it (together with positive class:bicycle values): GraphHopper Maps | Route Planner
The road has bicycle:backward=use_sidepath tagged which means that cyclists are not allowed to ride on the road in the backward direction and have to use the separatly mapped sidepath. See Key:bicycle - OpenStreetMap Wiki for more information.
I wanted to report this as a bug on the github page first but I wasn´t sure if this was intended so I wanted to ask here first.