[burritojustice]

Hi! I'm with Mapzen. Setting `use_roads` to zero means a preference for using roads tagged in OpenStreetMap that have bike infrastructure, as opposed to roads without bike lanes.

We don't route on sidewalks, and will avoid paths that are tagged `bicycle=no`. You can get a sense of these on our bike map. https://mapzen.com/bikes/

[bbarn]

Where is your bike lane data from? For example, the chicago loop detail on the linked page is incredibly (years now) out of date, and would send people down routes that have replaced bike lanes with dedicated high speed bus lanes.

[burritojustice]

We use data from OpenStreetMap, meaning you can edit and update information wherever you are, and changes will appear on the map in a matter of days.

[nradov]

Have you considered using data from the California Statewide Integrated Traffic Records System (SWITRS) in your routing algorithm? You can filter traffic collisions for those involving bicycles in order to identify roads or intersections particularly dangerous for cyclists.

http://iswitrs.chp.ca.gov/Reports/jsp/userLogin.jsp