Basecamp -> Zumo mileage change

[jfheath]

mImport - is the name given to a single character in a file on the Zumo which indicates whether or not the route has been created on the XT or has been imported from a different source.

(I used my moderator privileges to correct the typo in the above posts)

Imported routes behave very differently after the XT has recalculated the route as @Peobody described. Changing that single character (byte) in the file fools the XT to think it was created on the XT itself. Those routes have never showed RUT behaviour.

Nevertheless - if you want to be 100% sure that you follow the route you originally planned, then use the track and the route on the same screen.

Also - from Basecamp, change the name of the identical route and export it as a gpx file. Place that either in internal storage/gpx, or on the SD card in the gpx folder ( or is it garmin/gpx) this will act as a backup.

When transferring from Basecamp, do everything at the same time - or at least without disconnecting the USB cable between two separate transfers. That last minute - 'Oh I forgot to transfer a saved waypoint' is the killer. You go back to the computer, reconnect the usb cable and transfer the single waypoint. And that there is the disaster waiting to happen.

The reason is that transfer from basecamp writes everything to a single file (called temp.gpx). When you disconnect Basecamp from the XT, the file is closed and nothing else can be added to it. When you reconnect Basecamp to the Xt and transfer something else, a new temp.gpx is created. So all previous transfers are lost.

This is not an issue if you transfer everything at the same time.

You can of course import them into the XT - and they will remain on the XT. BUT when fiddling with loaded routes on the Xt screen,miles from anywhere, any changes you make deliberately or accidentally affect the imported version - the one that is saved on the XT. If you abandon the route and reload it - that version has changed. So you might want to reimport the original (from the temp.gpx file). . That is when you find out that it is no longer there to import.

Bottom line - transfer everything in one sitting, without disconnecting the USB cable.
And
Save copies (slightly modified name) as a gpx files and use a file explorer to place them in the gpx folder on the Zumo. The Xt cannot alter these.

[meagvg]

I hadn't any idea of the RUT issue. But surely have experienced it on the road. Apparently I'm one of those who thought it was an irritating "feature".
Thank you @Peobody for the inks to the fix. Spent a couple hours yesterday with the online Hex editor on 7 routes.

I've noticed for shorter trips, the mileage within BC very closely matches the Zumo. Two of the trips are 1000+ miles and two are 2600+ miles. Those are the ones with discrepancies. Since these are coast-to-coast IBA rides and not rallies I don't preplan stops. I just ride until I can't. Saves me from having to skip waypoints and deal with recalculation.

Thank you @jfheath for the backup and track overlay suggestions. More great ideas. I use Android file transfer to move files. I was burned once by not sending all files in one BC-Zumo session. Lesson learned.

Again, thank you to everyone for helping the new guy out. Greatly appreciated.

[rbentnail]

I use Android file transfer to move files. I was burned once by not sending all files in one BC-Zumo session. Lesson learned.

Again, thank you to everyone for helping the new guy out. Greatly appreciated.

This is why I NEVER transfer routes to the XT. I use exclusively the SD card. The XT's quirks of file management do not apply when using the card.

[Peobody]

This is why I NEVER transfer routes to the XT.

OTOH, I always do. On multi-day trips I will also put them on the SD card to have a safety copy. My process includes:
- Transferring to the XT
- Importing
- Loading to see if the XT calculates, and to confirm route accuracy
- Fixing the mimport byte.

The mimport byte fix has changed my routine. I used to put the routes only on the SD card, importing only the route being ridden that day but the mimport fix is to .trip files which requires that they have been imported. I have also had the experience of a route that the XT couldn't calculate on import. This led to the extra step of always importing, loading, and viewing on the map to confirm the XT could handle each route before I started the trip.

[meagvg]

The mimport fix changed my routine as well.

When storing GPX backups on the SD card, the Zumo doesn't recognize an operating system level file name change. When checking to import the "backups" from the card, all route names were duplicated. So another step was to change all the original route names in each GPX file with an editor.
And that worked. Now the SD card has the GPX backups with a file name I can easily read on the Zumo as a backup.

I'm probably missing something else, but thanks to you guys my routes are another level up on bulletproofing.

Leaving tomorrow, so no more messing with the Zumo. Putting on my Tetris hat and packing up the bike.

[Peobody]

When storing GPX backups on the SD card, the Zumo doesn't recognize an operating system level file name change. When checking to import the "backups" from the card, all route names were duplicated. So another step was to change all the original route names in each GPX file with an editor.
And that worked. Now the SD card has the GPX backups with a file name I can easily read on the Zumo as a backup.

The only thing I can think of that would result in the duplicate route names in the import list is if they were both on the card and in internal storage. A thing to know about the card is that any gpx file on it will never be modified by the XT. So, you send the routes to the card and then import them into the XT. The originals will remain on the card as a backup, available to be imported again. The imported versions get mimport fixed.

Safe travels!

[rbentnail]

I guess my routes are so basic that I have no need for any "fix". I just don't start the route until I'm ready to ride it and no problems whatsoever. Last weekend I rode from central NC, west then north to southeast WV, then to Cleveland, then back across the mtns to central VA, then to VA Beach, then home again. Not a single issue with the routing in 1617 miles. The XT itself is another matter.