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Today I took a 213 mile ride. For those of you familiar with North Carolina, it was an off-interstate loop from Charlotte through Linville and Little Switzerland. The speed limit reported on my XT was accurate less than half the time. Speed limit info has never been particularly reliable but it was exceptionally bad today. Went looking in the XT for a "seasonally closed road" avoidance. Didn't find one.

Not associated with the map is numerous incorrect traffic alerts and one reroute around what the XT showed as a closed road that wasn't closed. This was a section of the Blue Ridge Parkway.

These annoyances burnished the edges of an exceptional ride.

This is nothing new. I see this all the time. Part of the blame goes to whoever is supposed to report the changes to the company that supplies the map database to Garmin. Changes are made all the time. That is why you have to pay attention to your riding environment.

One quick example of how hard it would be to have 100% accurate speed limit info...

Years ago I worked for a regional planning agency. Garmin came and demonstrated one of the first portable car GPS units and obtained what is known as road classification data from us. It's basically what speeds and volumes the road was originally designed to accommodate. Garmin uses it as part of the ETA and "faster route" calculations. We could see right way that local speed limits were often lower than what the data suggested. We've all seen neighborhoods raise a big stink about "speeding cars" endangering their lives and convincing local authorities to put a lower number on the signs (which the local police are happy to support as it makes for more revenue).

I've been impressed over the years at how often the speed limit data in Garmin maps is correct, even catching it within a few dozen feet when the limit drops temporarily. I can't vouch for its accuracy around Little Switzerland, however, because even though I've ridden there numerous times, the scenery and the challenging, wonderful roads combine to "distract" me from the XT.

-dan

ray6576 wrote: ↑Wed Mar 08, 2023 2:43 am This is nothing new. I see this all the time. Part of the blame goes to whoever is supposed to report the changes to the company that supplies the map database to Garmin. Changes are made all the time. That is why you have to pay attention to your riding environment.

Understood and agreed. My comment is based on having ridden the same area numerous times with other maps and not having noticed as much inaccuracy as I did on this ride. I would welcome a feature that allows the turning off of the speed limit indicator.