Routing errors or unexpected long detours?
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:
1) 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
2) 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.
3) 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.
4) Bugs in the OFM or Garmin software
- Routing for Foot/Walking is broken when crossing tile borders in Basecamp and Mapsource. (This issue is solved in version 15/02/2014) Tile borders are recognized by a black border line across the roads. Solution is setting the avoidance for toll roads on. You'll see the same behaviour with other vehicle types when avoidance of
major highways/motorways are selected, but this should be turned off
anyway, even in bicycle mode!
- Please note that OFM is not 100% compatible with the latest Basecamp / GPS settings, so some settings are not "logical" and some workarounds are needed, see point 1) (this issue is solved in map versions 15/3/2014 and later)
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 (this issue is solved in map versions 15/3/2014 and later)
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.
Make sure the OFM version on your GPS is from the same date as the version in Basecamp!