For inexplicable reasons, riverside foot/cycle paths in Japan are often tagged as:
highway=footway
bicycle=yes
motor_vehicle=no
These are fantastic paths for cycling, but Graphhopper treats these as undesirable when routing for a “Racing Bike”. Is this something that can be accounted for?
The racingbike profile assumes that you want to go fast. A footway where a bicycle is allowed only without segrated=yes is annoying for a racebike. There are millions of these in cities which you will not like to take with a racingbike.
The paths in question are huge, wide, pristinely paved paths reserved for cyclists and pedestrians, but there are few of either. Personally, I think tagging them as footways is not the best. Years ago I tagged them as “cycle+foot path” but apparently Japan has their own way of doing things.