gravelsurfer wrote: I may be riding on the correct track/fire trail but the 550 thinks the road is 20 metres to the right. When I arrive at an intersection the Garmin is as confused and disorientated as I am. Has anyone else experienced this? Am I not plotting enough waypoints? Any advice would be appreciated.....
Pretty normal with all GPS's.
Its not the GPS that has the problem, they are extremely accurate, generally the accuracy is within meters and the Zumo is one of the more accurate units.
Its the maps that are the problem.
The accuracy of the maps especially for non suburban areas is a little poor.
If you have a look in google maps in satellite view (turn on roads) and find yourself something like for example Howes trail and Yengo or Blackfellows hand trail, zoom in and see how far out it shows the road from the actual trail.
Youll see what I mean easily.
I was travelling up Thunderbolts the other day and the road to the map was 100m off in spots

Hope that helps
