not confusing for symmetrical My Hamilton:
thanks, figured this out a minute or two before you posted. My method was to upload Strava .gpx to RideWithGPS, note that elevation error was also on RWGPS, so I deleted the downhill and told RWGPS to make me an out and back. Download and compare using the GPSVisualizer method.
Clearly a Strava bug.
Guess its good that BWR AZ got me to pay for RWGPS again 
On this theme, one thing I noticed is that it seems the behavior may differ between older routes and newer routes. I donāt know itās a route data error/accuracy issue or a change in some calculation on the Garmin side
I have a bike trail that is part of a number of my routes. A couple of these routes are at least 2 years old. I created a new one recently, using the same section. I noticed I was getting more climbs detected than on the older routes.
Similarly, with a different segment, I have two routes that share it. One detects the climb, the other does not. I have climb detection set to the most inclusive as Iām not the Ć¼ber climbers the rest of you are.
Itās not critical to me but it is annoying. Sharing this theory in case it helps with your investigation.
Interesting you mention this. Jeff (whoās done all the hard work on this) has commented over on the Garmin Forums āI think it might have happened in a 2 week window between the 29th of December and the 14th of Jan, but canāt be 100% sureā Since that time there have been issues. iirc my ClimbPro lag issues started prior to that.
ok, Mt Hamilton route was created by finding segment, finding someone that started near where I was going to start, and then copying their route to my Strava Routes.
If I create one by hand - this one took about 2 minutes - no elevation error:
Maybe the elevation error was introduced by the bike computer that captured the original route? And compounded by Strava not attempting to fix GPS data? I randomly picked a route to copy, have no idea when it was created.
I traditionally have used Garmin Connectās route editor to create my routes. It is far from bug free, but Iāve learned the quirks and I can make it work. I just tried to re-create one of my usual routes in Strava Routes and had to quit after just a few minutes of frustration.
Iām fortunate to have some great paved bike paths, that are long established. Garmin generally uses them just fine. Strava kept giving me convoluted routes and generally got confused. For example, one part of the route follows a river. I dropped a point along the path on the river ā Strava tried to put me on the other side of the river! The dot on the right is where I put the point; the endpoint is where Strava placed it.
Thatās roughly a 10-15m error.
I imported a file from ride with gps into strava and the sent it to my edge 830. Had issues mid ride after that. Typically Iām only using routes created in strava. Im wondering if the added step from rwgps has something to do with my issues.
I had an issue with ClimbPro at Rebeccaās Private Idaho last September. It got worse as the race progressed. I was guessing that it was a stacking error of some sort but never imagined it was caused by a sync from Strava to Garmin Connect.
Continuing to watch this. 
My workaround was successfulā¦ Exporting the GPX straight from Strava into GARMIN\NewFiles on a route was fine. Exporting Strava->Connect->Edge resulted in ClimbPro being out by ~300m after 10km. The turn-by-turn navigation was still spot-on.
For whatever reason it takes me 23 mins to explain and demonstrate this in a video. 
Hopefully itāll prompt Garmin to look into the issue. Even if the source of the problem is Strava, they should be able to handle it and not have their users have an extremely shitty time with their products. (and thatās putting it lightlyā¦ climb #2 in my video completes on one Edge before it really begins on another!)
In order to do this Iām guessing you have to have your device plugged into a laptop? Canāt do it from phone to device?
Thanks
Maybe of interest but after reading this thread I thought I would do a test.
I took a random route that was created in Strava and exported to Garmin connect and just selected āduplicateā on the Garmin connect website.
The duplicate that it created moments later has different elevations.
I assume that the duplicate is using elevation correction but could be wrong?
Could be interesting to see which of the two plays nicer with climb pro?
Nice video 
I just needed an excuse to go for a long ride today.
Thanks for bringing all the work together (and having a nice ride at the same time)
Just to mention here:
I donāt think that this is an Strava topic. I can see the same effect using Tracks from komoot.
So I think the import to Garmin Connect seems to be the issue.
Koomot is a whole new problem of smoothing elevation data. They were caught in the cross-fire of my deep-diveā¦ and might be the topic of another video if I can prove their exports are junky too.
Hi and thanks for your reply.
Please have a look on my plot of the same 100km route. One from Garmin Connect, the other one from komoot directly.
For me it looks like the same topic, what do you think?
Yeah, about 1/3 into that route the elevation shiftsā¦ and gets worse towards the end. Thatād cause issues with ClimbPro for sure.
This will be food for thought at Garmin HQ!
Has anyone noticed that routes made in Strava have really precise elevation data where routes exported with RideWithGPS and created in Garmin directly smooth over the data.
I havenāt switched to the new roaming update for the 1040, just switched my source of data.
Feels like a whole new world when just using the map w/ elevation at the bottom.
Thatās maybe the bug that @GPLama was describing. I think I found it too on my recent trip to Spain. The routes from strava were pretty precise but the Garmin routes triggered climb pro off circa 0.2mi after the actual crest.
