Interesting: Note that OSRM thinks you can cycle contraflow along greek street https://www.openstreetmap.org/directions?engine=fossgis_osrm_bike&route=51.51340%2C-0.13043%3B51.51321%2C-0.13029#map=19/51.51330/-0.13036&layers=N but there's no evidence to allow it. Graphopper interprets it correctly as tagged, giving a longwinded diversion https://www.openstreetmap.org/directions?engine=graphhopper_bicycle&route=51.51321%2C-0.13029%3B51.51340%2C-0.13043#map=19/51.51301/-0.13110&layers=N. That has got to be an OSRM bug but it's unlikely that anybody involved with OSRM will see it here. I presume https://github.com/Project-OSRM/osrm-backend/issues is the correct place to report it.