Garmin 810 barometric altimeter discrepancy

riddon

I have been having a protracted discussion with Garmin about an issue I have found with my 810. (it takes them 2 days to reply to every email). Whenever I stop for a brew, I pause the unit and switch it off so that I don't accidentally press something when it is in my pocket and lose the ride or something like that. I usually take it off the bike for security and pop it in my pocket. When I start riding again I switch the unit back on and press the start/pause button to recommence the ride. The issue I have is that at every stop, the elevation takes a large vertical jump, usually upwards which makes a nonsense of the data I get at the end of the ride on garmin connect. I think this jump is related to the fact that the unit warms up quite a bit in my pocket. In order to get a half sensible reading, I have to use the elevation correction feature in Connect so there is not much point in having a barometric altimeter.

Anyone else noticed this and any suggestions for a fix?

grenw

Never seen this on my 510 which I've taken off a few times over the past few weeks when dealing with punctures. I see the temp jump but never any elevation change. I leave it switched on though and just let the auto pause do its stuff.

My 510 also reads around 15%-20% more than my wife's 810. My legs tell me the higher number is right

northcliff66

I can understand taking it off the bike if you are worried about theft.

That aside, why not just leave it on the bike switched on? I do that, without autopause on and the battery lasts way longer than my body.

The only downside is average speed readings, but those don't mean anything anyway.

The upside is consistent data and you never get thst "Oh crap" moment when halfway home you realise you have forgotten to turn it back on.

riddon

I think if I left it on the bike it wouldn't be long before it wasn't there when I came out of the cafe. Everyone around here takes their Garmin off, some folks even take their saddle bags into the cafe with them.
I will try leaving it switched on and just hope I don't accidentally push the screen and lose my ride, that seems to give me better elevation readings. I did have a 'touring plus' before and would regularly run out of battery on long rides but the 810 seems much better. Hopefully it will outlast my legs.

Guernsey Donkey

On my 810 I just use auto pause and stick it in my pocket at cafe stops. I've never had any altimeter issues.

slowmart

Have you tried auto pause?

its trouble free, no loss of data or average speed if you stop for whatever reason






Or RTFI

redvee

No need to turn it off to stop accidental screen presses, there is an option to lock the screen accessed via power button. A quick press of the power button and a padlock symbol is shown bottom right, press it. Do the same again to unlock the screen.

riddon

Ah! I had missed the lock screen option. That would be the answer then.
Thanks to all for your suggestions.

chris_bass

on my edge 1000 when i turn it on it says "elevation set to XXXX" you could see what it says your elevation is when you stop and see what it says when you turn it back on?

adrenalnjunky

I don't trust those anyway. On my 500, I will ride with a friend with a 500, and we'll have elevation differences for 200-300 feet.

I dropped mine and cracked the screen, and garmin sent me a replacement. That one is closer to my buddy's 500, but we're still off and probably never more than 50 feet apart for the 20-30 miles overall.

Giant04

Hi
Everyone I know with a garmin has or has had this problem
One of my friends is a genius on all things garmin (and strava) and he says it's down to the air pressure change
If you try waiting till your back outside again before switching this should help
Or if you use the same coffee shop all the time you could try setting an altitude point in your settings so your garmin calibrates to that whenever you swirch your garmin back on?

alex222

Have the same issue with my 500, I try to avoid turning it off now on stops. Will certainly try the tip above in terms of waiting until outside for a while before setting it going again.

topcattim

Giant04 wrote:

Hi
Everyone I know with a garmin has or has had this problem
One of my friends is a genius on all things garmin (and strava) and he says it's down to the air pressure change
If you try waiting till your back outside again before switching this should help
Or if you use the same coffee shop all the time you could try setting an altitude point in your settings so your garmin calibrates to that whenever you swirch your garmin back on?

I have the same effect, and am grateful for redvee's advice, which I've not seen before.

redvee wrote:

No need to turn it off to stop accidental screen presses, there is an option to lock the screen accessed via power button. A quick press of the power button and a padlock symbol is shown bottom right, press it. Do the same again to unlock the screen.

My 810 is quite prone to turning itself off and then when it eventually finds satellites again, it gives a ridiculous altitude. So I correct this by entering a manual figure (taken using the MyAltitude app on my iPhone) into the option that you get when you press the satellite icon in the top bar, then "satellites acquired">set elevation.

You could do this manually when you come out of your cafe stop, or as Giant04 says, you could enter the cafe stop as a location and enter the altitude manually there.

itboffin

Mine does the same, doesn't happen with my vivoactive or 705

Garmin's testing team has to be the worst ever

redvision

The barometric readings can be affecting by a number of things: as said above, going from inside to outside, the weather etc.

Could also be an issue with the device itself though.

As I have said over and over, the 810 is a great device when it works but I found it to have to many persistent issues.