What is it with the Zumo?!?!

[MMC]

Bloody thing. It's always the same:

Let's say arrival time is 1000. As I ride, it slowly clocks up more and more minutes, until it's about half an hour after the initial arrival time.

Then, around 30 miles from the destination, the damn thing decides to get ansy and throw me down every single tiny back lane it can find. Meanwhile, it gleefully starts telling me I'm going to be later and later.

Drives me skitz. Does anyone else's do this?!

 

[SilverFish]

I think all the GPSs Ive had over the years had the same tendancy to understimate the journey time at the start, and then frantically try to add in a few minutes the closer you get. Normally it is only a few minutes on a journey of upto an hour.

I think its because they assume a perfect ability to maintain progress on every road type. So for example, the local streets around your destination would be 30mph, whereas there may be a back lane which is in the NSL, and therefore 60mph, and so on. It would still prefer this route if it was slightly longer, windier etc, over a route which though more direct and straightforward, had a slower speed limit and therefore technically a longer journey.

They also dont take into account traffic, weather and other road conditions which would prevent you from safely sticking to the posted speed limit.

Of course if you've set your preferences to avoid Highways and Trunk Roads than all of the above is bunk!

Cheers,

Mike

 

[John Armstrong]

They also dont take into account traffic, weather and other road conditions which would prevent you from safely sticking to the posted speed limit.

Assuming that the Zumo uses the same Mapsource as the SP3 / 2610 / 2820 then the notional speeds are not the "speed limits" eg motorway default calculation speed is 67 mph.

However, the later GPS's are clever enough to know what sort of speed you average over the classifications for the types of roads in it. So if you always do 40 mph on the motorway the GPS will use that speed if it recalculates the remainder of the journey, otherwise it will use the 67 mph if the route was transferred from the PC and will continue to do so until you reach the destination or go off route and it recalculates the journey.

Does this help MMC? BTW saw your letter in M S & L

 

[GS TRV]

Just ride faster

 

[ECM]

Then, around 30 miles from the destination, the damn thing decides to get ansy and throw me down every single tiny back lane it can find. !

Could it be you got your -speed- and/or - avoidence- settings not to your likings, but without realising it??

 

[richie]

Ive been using the GPS60C for the last four years and its ETA are amazingly close, but I dont live in the UK

 

[(RIP) Tunneruk]

Sell it and buy A TT Rider V2. I did and it's the best GPS move I made!

 

[Angus]

No problem with mine, if I i boot it, can shave a couple of minutes off the initial eta displayed. Usually though I plug it in, read the eta and realise I am going to be late..

 

[judge]

Bloody thing. It's always the same:

Let's say arrival time is 1000. As I ride, it slowly clocks up more and more minutes, until it's about half an hour after the initial arrival time.

First bit sounds like normal behaviour to me, it calaculates your ETA based on the settings for speed in the unit, then it adjusts to the 'actual' ground covered, mostly it'll be later, rarely it will be earlier.

Best to set it for a pessimistic average and arrive early than late.

Then, around 30 miles from the destination, the damn thing decides to get ansy and throw me down every single tiny back lane it can find. Meanwhile, it gleefully starts telling me I'm going to be later and later.

Drives me skitz. Does anyone else's do this?!

Not normal, are you certain it deviates from the originally planned route? Next time review the whole route from the turn by turn screen then ride the route and see if it changes without you having gone off-route. Doesn't sound right to me

Just give Desmond Decker another playing and chill a bit

 

[Tramperman]

My garmin Quest2 tells me to have my breakfast before I go to bed, then I wont be late arriving next day!!?

 

[Bumpkin]

Sell it and buy A TT Rider V2. I did and it's the best GPS move I made!

Until you need customer service

My i3, Quest and 2720 all do a reasonable job of estimating the ETA, usually a few minutes get added unless the roads are really clear. The 2720, when used in the car and plugged into the GTM10 receiver, makes adjustments to ETA depending on traffic holdups on the route.