Bicycle trekking profile routes through a way with bicycle=no

[AnthillSudoku]

Hi,
brouter-web send you on a way with bicycle=no when making a route between "Zambana Vecchia" and "Sarche" with the default profile "bicycle trekking":

route

way 1247751485 with bicycle=no

Thanks

[poutnikl]

It is not a bug, but intended feature of built-in and most of the 3rd party (like mine) profiles.

The reasoning behind that is viewing bicycle not as a vehicle with allowed/forbidden passage, but as a biker with a bicycle, by default traveling mounted. But another legal transportation mode on short distances is a dismounted biker pushing a bicycle, considered by most of traffic laws as a pedestrian.

It is frequently used if some passage has forbidden bicycle passing, or if traffic or physical conditions do not allow safe riding. Typical example can be some pedestrian only bridges or areas, some jammed narrow passages with mixed/pedestrian traffic, or taking some pedestrian shortcut with substantial saved distance.

Such forced fallback to pushing mode is adequately punished by high costfactor - see the screenshot. 9050 means than the given way alement is taken as if it were 9.05 times longer ideal road for bikes. By rough estimation, the pushing shortcut is preferred only if it takes less than about a half of time, compared to a mounted detour. And there can be the last resort cases the bicycle=no segment is the only possible way. You would not want to return 10 km just because there is a pedestrian only bridge.

The solution could be introducing a flag/option like "hard_bicycle_no=yes" in profiles. Both soft and hard approaches have their pros and cons and cases where they fail miserably.

• The soft one may fail by leading to passing long and forbidden segments.
• The hard one may fail by leading to avoiding short, easily passable segments.

More elegant solution, but IFAIK not currently possible with current profile code syntax, would be implementing pushing distance threshold, not allowing passage of segments longer than this value. But the implementation could be tricky, as OSM may code it as a series of way segments.