2.21 Why the XT Alters Your Route

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….what is going on and how to stop it

When a route is transferred and imported, the process should be fairly quick. There will be a little calculation going on, but rarely more than a few seconds.
If it takes longer than that (say 15-30 secs), then it is doing something that it shouldn’t need to do. This next technique is something that you may need to do once in a while to make it obvious if your entire route is being re-calculated on transfer.


  1. Create a simple route on BaseCamp between two points that are just a mile or two apart. Make their positions relative to each other very obvious - say East and West of each other. See Pic 1.



  2. Add a couple of extra points using the insert tool to make the route take an obvious detour - eg to the north. If you have used the insert tool, then they could be Shaping Points or Via Points. I’ve circled 3 added points - see Pic 2.



  3. Double click the magenta route line to display the Route Description box (Pic 3). Note that two of the points have ended up as Via Points. Right click these and select ‘Don't Alert on Arrival (shaping point)’. This gives Pic 4. All shaping points except for the start and end. This is what we want.

  4. Right click on the route (magenta line or the route name) and select ‘Remove Shaping Points’ . The route description will now look like Pic 5 - with no Via Points and no Shaping Points.
    But the magenta line will remain in the same position as in Pic 2 - it is held in place by what I call the Ghost Points.

  5. Transfer the route to the Zumo XT, Import it into Trip Planner and display the map.

The map should show the route with the long detour to the north, just like in Pic 2. If it shows a direct route like Pic 1 , then the route has been recalculated by Zumo.

If the route recalculated with this simple experiment, then it will happen for every route that you transfer and import until you sort out why it is happening.

Check that your maps are identical.

Check that the option boxes in Edit -> Options -> Device Transfer are unticked in BaseCamp.



Normally, of course, you would not strip out the Shaping Points. These are designed to keep the route on the roads that you want. However, it is not a good idea to put a lot of Shaping Points in place. These prevent the satnav from finding different routes should it ever need to. Careful choice of a few shaping points can often work better than having lots of them. Unless you have lots of alternative backroad routes or you route keeps trying to head for a Motorway.


You can check what Zumo will do to your route by forcing the entire route to recalculate

On the Zumo, import a route, and select it so that the route description is displayed, you can use the Tool menu to edit it. Select ‘Change Transportation Mode’ and choose ‘Car’ instead of Bike. The route will recalculate and you can see what changes might take place should you go off route during your trip.

But it may be easier to change settings in Basecamp - that will give an approximation. Hint - change the route profile from motorcycle to Custom to try this and change it back when you have finished.

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The information on these pages has been acquired from personal experience of using and testing the behaviour of Basecamp and my Zumo XT. I have no links with Garmin, and these pages should not be regarded as instructions. They are presented for interest only. The contents of these pages must not be shared, copied, transmitted, redistributed or re-published in any form without my permission. (C) JHeath 2021.