How to adjust GPS average speed to make ETA close to actual

[Peobody]

but it is rare to see it alter by much unless your riding style changes or reported traffic gets in the way.

When it quickly alters by any significance you can bet that a road closure has been detected ahead resulting in a route change. Unfortunately, the XT does not show you the location of the closure so its best to stop, use something like Google Maps on your phone to identify the closure, then determine whether the route created by the XT is reasonable. I have experienced false closure detections as well as absurd route modifications in response to detected road closures.

[jfheath]

Good point, @Peobody .

I take absolutely no notice of road closures announced by the XT, mostly I am right, and it is 'wrong'. Just Occasionally the other way around. But if it thinks there is a closure, it recalculates to avoid it. No choice with the XT last time I encountered one.

Actually, road closures are often reliable, if they are in the period of closure - but I have observed them to be closed a few days too early and closed long after they have been cleared. Once, even for a one day cycle race.

The information is sometimes to vague - the satnav avoiding the A6 because there was traffic and road works. Yes there were, but not on the section of the A6 that I was riding. It didn't know that.

I make my judgements on websites that have more upto the minute than Drive has access to. Or smartphone link in the case of the 590/5

I often use theaa.com website for Uk roads.

[Peobody]

But if it thinks there is a closure, it recalculates to avoid it. No choice with the XT last time I encountered one.

Yup! No notice. In fact, the last time it happened to me, the only way I knew about it was that hours had been added to arrival time. There was probably a verbal alert but I ride with spoken navigation turned off so would not have heard it. This is another gripe with Garmin developers. If spoken navigation can be turned off then every audible alert should include a visual component.

[jfheath]

Unfortunately, the XT does not show you the location of the closure.

This is something that i would have agreed with until this last year. I had to stop at the side of the road as the XT screen was displaying a red circle with a white centre, and I didn't know what it meant. I assumed a road closure, so I continued to investigate. Indeed it was closed - the entire high street of a Yorkshire Dales town was closed for a few weeks. I noticed it again when a bridge in another village (both of these were on my local RUT testing route) ! I've seen them more frequently recently - but so far they have been for long closures.

Presumably picked up by Drive. I'll come back with a screen shot if I can find one.

[jfheath]

I'm aware that I have hijacked the original thread - unintentionally. The original poster has a Zumo 550, and traffic considerations do not affect that particular device - from what I remember - it was so long ago that I had the 550. I think we have answered @Florida Red Wing's queries about the 550 - but if not please post back !

But traffic on the 590, 595 and XT (and probably some of the other 34x and 39x Zumos) is a topic worth talking about - so I have started a new thread about the traffic display and what is available on the Zumo XT screen here viewtopic.php?t=2614

Anything to do with traffic or road closures, please post to the new thread.