It’s a funny one and your guess is correct – the way Garmin Connect works is just by getting a track (polyline) from c.t without any accompanying turn instructions at all. Garmin then retrofit their own turn instructions to the track: I’m not sure how they do that but my guess, which tallies with your experience, is that they just look at the angle of turns. It seems an odd way to do it but that’s the way Garmin Connect has chosen to work.

If you download a TCX from the website, then that comes with c.t’s own turn instructions included.

Having read the comments by Psamathe and Richard, I thought I would experiment a little to see what differences, if any, I could find in a route that comes from c.t via Garmin Connect and the same route from c.t with file downloaded to windows computer and then pasted into the Edge 1040. Having created the route in c.t I saved it with a slightly different name so that I could have both routes on the Edge. I rode both times without the map screen, so I was relying on turn directions popping up.

In terms of navigation, the only difference I could see was that the route direct from c.t showed the road name at the bottom of the screen for a few seconds when I joined a new road. This did not happen with the version via Garmin Connect. Both versions did not give any information about a right turn at a T-junction. I have noticed this before and I think it might be something that could be corrected. The route is https://cycle.travel/map/journey/648063 and the missing turn comes immediately after via point 27.

In terms of elevation, with the route direct from c.t the Edge thought there were 6 climbs. As I approached the climbs, climbpro popped up looking normal, coloured gradients, etc. However, as soon as the climb started all this was replaced by a horizontal line and no colours. At least four of these 'climbs' were so insignificant that I do not believe they would pass the Garmin criteria for a climb and they do not show up as a climb in non-navigation mode. With the version that came via Garmin Connect the Edge thought there were 2 climbs. Only one of these was included in the c.t climbs. They displayed as I would expect and the also appear as climbs in non-navigation mode.

Since it became possible to send routes via Garmin Connect that has been the method I have used, so the last time I pasted files into the Edge was a while ago. This was an Edge 530, but I don't recall having any problems with elevation.

Anyway, I wonder someone could try to replicate this, as it might just be me, my computer or my browser (Firefox).

"Both versions did not give any information about a right turn at a T-junction. I have noticed this before and I think it might be something that could be corrected."

This is one of the issues I noticed though as it was a 1200 mile tour, I particularly noted the straight-on junctions. But I did see the T-junction/X-road no directions on occasions (becomes a question of degree as straight on to 90 degrees is a continuum).

I wondered if it was an OSM issue where the "give way" vs bend with turning is not set correctly.

nb I was in France, Belgium and Netherlands but mostly in France.

Ian

Believe it or not, give way information usually isn’t recorded in OSM, so c.t has to take an educated guess – usually it gets it right but not always. I’ve got a couple of small refinements in the works for this but it won’t be a 100% reliable solution unfortunately. 

The problem with this T-junction, https://cycle.travel/map/journey/648063 (immediately after via point 27) is that it's not just about giving way. You have to turn left or right and to do so have to get in the correct lane. The turn has traffic lights so you do not necessarily have to stop. My route from cycle.travel gives no direction irrespective of whether the route has passed through Garmin Connect or been downloaded and pasted as a file. The only way to know which way to turn would be to have the map page showing.

I have used cycle.travel routes that include other T-junctions and normally a direction pops up on screen. There seems to be something about this one that cycle.travel is not recognising.

Do you mean the turn from the King’s Drive onto Torbay Road?

If so then cycle.travel is definitely recognising it as a right turn – you can see that in the turn-by-turn directions (instruction number 85 on the website). If you use the cycle.travel app, or download a TCX course (which includes c.t-generated turn-by-turn instructions), then it will be in there.

It sounds like maybe this is a Garmin issue. If you use Garmin Connect, or a GPX track, then any turn-by-turn instructions you see will have been generated by Garmin – not c.t. 

Thank you, Richard. Yes this is the turn. I had previously noticed it in the listed turn-by-turn directions. However, whether the route comes to the Edge 1040 via Garmin Connect or as a pasted file (TCX) nothing pops up on the screen. If I have the map page on, the screen shows distance to the next turn, but this turn does not seem to register. This is not a one-off. This junction is on my way home on a number of different routes and it has never popped up. Probably a Garmin issue, but it is very strange.

Hi Richard. I've done a little investigation which may explain what is happening here. On cycle.travel turn-by-turn directions it says, Turn right onto A3022 Torbay Road. I have just looked through the list of directions on the Edge for the route saved via Garmin Connect and the route with the pasted TCX file. For both of them it says,  Keep right on the King's Drive. The next direction involves the cycleway which is 86 on cycle.travel. This may explain why I think I've never seen it, as presumably it appears and disappears some way before the junction. As this section is downhill, fast and frequently busy I am probably not looking at the screen. Why it should be different from what is written on cycle.travel will probably have to remain a mystery, although getting in the correct lane early means that you don't have to worry about the turn when you get there. Anyway, thank you for your help and, as always, appreciation for your work.

"Believe it or not, give way information usually isn’t recorded in OSM, so c.t has to take an educated guess"

That is a surprise. But thinking about it a lot of mapping doesn't include giveway eg IGN who I believe have released a lot of mapping to OSM. Also any mapping taken from aerial or satellite data won't include "give ways". I guess you need somebody who knows the locality.

I'm surprised OSM are not adding it given how much routing is done using their data.