Once in a while you will see that the GPS refuses to calculate a route, make long detours or just draw a straight line between the start and destination of a route. There can be several causes for this behaviour:

Settings in the GPS unit or Basecamp/Mapsource are not correct / optimal

• • Read the other Tips & Tricks sections to setup your GPS

  • Don't avoid highways/motorways

  • Don't activate multiple routable maps

Broken road network on Openstreetmap

• • The OSM database is changing a lot, the road network is improved but also editing errors are made

  • Report those errors in the "note" menu on openstreetmap.org or become a mapper and repair it by joining the osm community

  • Because of the many updates on osm, there can be differences between the OFM updates. So therefore it is important to use the same map version (=date) on the GPS as on the pc and recalculate old routes that were made with a previous version.

Routes are too long to calculate

• • Basecamp and Mapsource can calculate longer routes than the GPS. Dont make the route sections too large, 20 km between viapoints should be ok, >100km often not.

Car routing is not supported

• • The Openfietsmaps are not suitable for car navigation. Motorways and other roads that are blocked for cyclists are non routable.

Limited use for Walking/Hiking navigation 

• • The maps are not optimal for walking/hiking. Some roads that are accesible for pedestrians but not for cyclists can be non routable (e.g. a motorway with a sidewalk). Some paths are not routable (bridleways).

Device transfer options (Basecamp 4.3.3. and later)

• • Dont select any option! Especially "Always match route to the map" can cause broken routing (straight lines) when selected.

Different OFM version on GPS and Basecamp

• • This will cause errors when making a route in Basecamp and transfer it to the GPS.  After route calculation this can result in straight lines.