Cycling UK Forum

Tangled Metal wrote: ↑30 Sep 2021, 10:15pm ..........

It I was buying one, might be soon, I'd get Montana 700i or satmap a20. The former is better overall but the latter has the better screen.

Phones have their uses but I do not believe the gps antenna is as good as the quad helix one in gpsmap66 range. Plus without the full ABC ( altimeter, barometer and 3 axis electronic compass). Hiking or offroad I've wanted to get height accurately for navigation reasons a fair few times.

Phone GPS accuracy might be 5m. GPSMap64S/66S will be about 1.8m. Does anyone use the GPS to say which side of the road to ride along ?

I'm also not convinced that an electronic compass is useful on a bike. A GPS based one will give orientation with a move of 5m or so...

Altimeter, on a bike handlebars will be erratic due to variation in air pressure due to movement through the wind(*). It will give a height reading, but so will GPS satellite altitude (to about 20-30m). The extra accuracy (provided one understands how it can go wrong!) might useful for cross-country mountain biking, but really question where that level of detail on a road helps with navigation.


I think the GPSMap range of devices are excellent for hiking, mountaineering, ski-touring, etc.. That's why I've bought one a few weeks ago. But on a bike they're a so-so device, with many others offering much better options. If primary use is in the hills, then to save buying a second device its OK on a bike.. (I'd also suggest getting the "TalkyToaster" Open Streetmap data alongside any OS map data - being able to jump between the two (use profiles in the GPSMap device) is very useful ).


(*) I have a brand new GPSMap64S. Its first week of serious walking was last week. One example day involved 1000m of map contour counting assent over a couple of Munros. The weather was blowing a strong wind (gusts to 40-50mph). GPS in mesh pouch on front strap of my rucksac, so exposed to the air changes. The altimeter recorded 1650m of assent (60-65% more than true assent), and the assent track record showed a spiky-hedgehog pattern of random movements up/down (as would my ancient and no-longer waterproof Garmin Vista Cx, so no significant change in how the devices performs on that detail in 15+ years). A bit of computer based post-processing of the recorded track got the height gain down to a believable 1050m of assent.



- Nigel

Mick F wrote: ↑3 Oct 2021, 9:46am Garmin Montana.
I cannot fault mine at all, and if it broke, I'd buy another.
Expensive, yes, but worth their weight in gold IMO.

Expensive and heavy. But that will all come out in the option appraisal.

But we still don't know the uses the OP is considering, nor how a big a screen is required.

Jonathan

At risk of muddying the water slightly, I think what's as important as choosing a device, is gaining a thorough understanding of how the device, once chosen, works. For example, it's taken me an age to get to grips with Satmap's software, but now I'm there, I can navigate safely & readily, whereas for the first couple of years (yes, I really am that slow a learner! ) I was often stymied by not knowing how to get the best out of it.
The above paragraph can of course be summarised by the phrase, "Read the manual."!

simonineaston wrote: ↑3 Oct 2021, 11:39am At risk of muddying the water slightly, I think what's as important as choosing a device, is gaining a thorough understanding of how the device, once chosen, works. For example, it's taken me an age to get to grips with Satmap's software, but now I'm there, I can navigate safely & readily...

Definitely. And this isn't said often enough. Also applies to maps, compasses, lichen on trees...

... and probably muddied water if you were Polynesian.

And to advice to others.

Jonathan

Depends where you are. I had some very experienced mountaineer friends who fell through a cornice in bad weather. That's where 5m isn't good enough. They survived through pure luck. I've been in the hills where 5m of inaccuracy could have issues. Cycling on roads less so but perhaps mountain biking in the hills might be an issue too. I've seen MTBers cycling a single track a little wider than the pedals and steep slope above and even steeper below. Miss that path and....

It's true we don't know much of what the OP needs but we do know two things he wants, GPS unit that's not a phone and 50k scale mapping. For that a phone isn't part of his plan for navigation. Satmap or garmin Montana are the best gps unit option for mapping. Money an issue then satmap20 might be better of the two or an even cheaper option.

Nigel wrote: ↑3 Oct 2021, 9:55am Does anyone use the GPS to say which side of the road to ride along ?

Here's a trace from my Montana.

Up the hill turning off to the north, and later coming back from the east.
My Montana with a clear view of the sky, is accurate to less than 8ft.

Tangled Metal wrote: ↑3 Oct 2021, 1:34pm Depends where you are. I had some very experienced mountaineer friends who fell through a cornice in bad weather. That's where 5m isn't good enough. They survived through pure luck. I've been in the hills where 5m of inaccuracy could have issues. Cycling on roads less so but perhaps mountain biking in the hills might be an issue too. I've seen MTBers cycling a single track a little wider than the pedals and steep slope above and even steeper below. Miss that path and....

It's true we don't know much of what the OP needs but we do know two things he wants, GPS unit that's not a phone and 50k scale mapping. For that a phone isn't part of his plan for navigation. Satmap or garmin Montana are the best gps unit option for mapping. Money an issue then satmap20 might be better of the two or an even cheaper option.

I've heard of hikers walking 5m or so to the side of an obvious trail because "that's what the GPS shows". Surely in both these situations, and with any map, the evidence of your eyes trumps what the map says.

the evidence of your eyes trumps what the map says.

I get the idea, as an example of the importance of navigational accuracy, but agree analogue over digital, for sure, up on that icy ridge !

Bmblbzzz wrote: ↑3 Oct 2021, 2:26pm

Tangled Metal wrote: ↑3 Oct 2021, 1:34pm Depends where you are. I had some very experienced mountaineer friends who fell through a cornice in bad weather. That's where 5m isn't good enough. They survived through pure luck. I've been in the hills where 5m of inaccuracy could have issues. Cycling on roads less so but perhaps mountain biking in the hills might be an issue too. I've seen MTBers cycling a single track a little wider than the pedals and steep slope above and even steeper below. Miss that path and....

It's true we don't know much of what the OP needs but we do know two things he wants, GPS unit that's not a phone and 50k scale mapping. For that a phone isn't part of his plan for navigation. Satmap or garmin Montana are the best gps unit option for mapping. Money an issue then satmap20 might be better of the two or an even cheaper option.

I've heard of hikers walking 5m or so to the side of an obvious trail because "that's what the GPS shows". Surely in both these situations, and with any map, the evidence of your eyes trumps what the map says.

Not sure, I think that stretch was fed into by a flatter, boggier stretch without paths. As daft as it sounds a group I was in one 7, not doing the navigation too many got involved for my liking, found themselves the other side of the mini gorge to the path in question and the navigators tried to get us to cross direct to the path. I and another guy ignored them and went around, along with most of the group. Some people just shouldn't be let loose with a map or gps! It wasn't long after that the other guy with the common sense set up a navigation training day being a qualified ML. He asked me to help. Not something I'd do as I'm untrained and know I have my own navigation issues at times. It's not foolproof with all the gear you can get and even the experienced get it wrong at times.

In this area I mentioned it's easy enough to miss this path if you're only using your eyes. I've got "turned around" a few times by missing paths over the years.

simonineaston wrote: ↑3 Oct 2021, 3:05pm

the evidence of your eyes trumps what the map says.

I get the idea, as an example of the importance of navigational accuracy, but agree analogue over digital, for sure, up on that icy ridge !

Although one time we were out walking on relatively benign, not particularly high moorland. It was snowy, the paths ill defined & the terrain rather featureless for getting good old fashioned compass bearings.

The situation suddenly became more "interesting" when clouds suddenly rolled in - we went from sunshine to whiteout in a couple of minutes or less. I was grateful for the OS maps & GPS on my phone to use to backtrack our route, along a close approximation of the footpath/bridleway we had nominally followed, off the moors.

RickH wrote: ↑4 Oct 2021, 8:27pm

simonineaston wrote: ↑3 Oct 2021, 3:05pm

the evidence of your eyes trumps what the map says.

I get the idea, as an example of the importance of navigational accuracy, but agree analogue over digital, for sure, up on that icy ridge !

Although one time we were out walking on relatively benign, not particularly high moorland. It was snowy, the paths ill defined & the terrain rather featureless for getting good old fashioned compass bearings.

The situation suddenly became more "interesting" when clouds suddenly rolled in - we went from sunshine to whiteout in a couple of minutes or less. I was grateful for the OS maps & GPS on my phone to use to backtrack our route, along a close approximation of the footpath/bridleway we had nominally followed, off the moors.

If you don't have a handy horse then that's a good effort.

RickH wrote: ↑4 Oct 2021, 8:27pm

simonineaston wrote: ↑3 Oct 2021, 3:05pm

the evidence of your eyes trumps what the map says.

I get the idea, as an example of the importance of navigational accuracy, but agree analogue over digital, for sure, up on that icy ridge !

Although one time we were out walking on relatively benign, not particularly high moorland. It was snowy, the paths ill defined & the terrain rather featureless for getting good old fashioned compass bearings.

The situation suddenly became more "interesting" when clouds suddenly rolled in - we went from sunshine to whiteout in a couple of minutes or less. I was grateful for the OS maps & GPS on my phone to use to backtrack our route, along a close approximation of the footpath/bridleway we had nominally followed, off the moors.

In a whiteout the evidence of your eyes can be deceiving.

Christopher Lycett wrote: ↑29 Sep 2021, 10:05am Which stand-alone GPS device(s), with 1:50,000 UK pre-loaded, should I consider? I don't have, and don't want, a smart phone.

I have an old Garmin 810 and would be happy to update it with another 'Garmin Edge'. Features wise the Edge® Explore has all I'd need although the extra battery capacity of the Edge 830 would probably sway me (upto 20 v 12 hours). Yes the 830 is more of an investment but my old 810 has lasted 8 years which is not bad for a piece of tech'; which for me would also be a consideration when justifying how much I am prepared to treat myself.

The 530 is cheaper and also has 'upto 20 hours' battery life. I do find the 830 touch screen far more intuitive to use than the 530's buttons, plus the deal breaker on my 810 is that the power button has failed; although admittedly that was after seven years and even now I am currently still using it all be it with a home made button; that to be fair has lasted nearly a year so I will probably not replace it until I have to!

I recall with sadness the death of a fellow student back in the 1990s, after a fall in Snowdonia. As the sec. of the same university's Climbing Club, I attended her funeral. The individual concerned was with a group from another student club. The group got into difficulties and her fall was a consequence. The mountain rescue team cited navigational errors and I've often wondered whether a GPS device may have contributed to a different outcome. However, it's just as easy to misuse a GPS device as a paper map, I suppose...

Buy an old android phone and load an app using WiFi and like others have said, don't put a SIM card in it. Probably the cheapest option by some considerable margin. Also buy a gel case like in the picture and punch a few holes into it and strap it to your bike with cable ties.