I have a Garmin 500 that I've been using since early this season. Lately, like on the last couple of rides, the elevation data it compiles has shown an odd little anomaly that I wonder if anyone else has experienced. On both of these rides, I stopped at local cafes, turned off the timer (but let the unit power itself down) and grabbed a quick bite to eat, staying there for maybe 20 minutes or so. WHen done, I get back on the bike, power up the unit, restart the timer and continue on my way. Once home, I upload the data to the Garmin site, and to Strava, and both shown an identical jump in elevation that bears no resemblance to the actual terrain - like a 300' cliff face on the graph. On close inspection, I find these have happened at the point in my ride where I stop to eat and the computer is inactive.
Anyone else have this happening? Any ideas? I've had this happen with the temperature data because the unit has been sitting in the sun, but never with elevation. In neither case was there a change in weather while I was stopped, so I don't think any atmospheric pressure differences are accounting for it. I never really relied too much on the elevation data to begin with, but with Hilly Hundred coming up in a few weeks, I'd like to think it would give me some more realistic data.