Mountain Biking Activity MTB - Distance overstated by 10%

Is anyone using their Descent with biking, specifically mountain biking activity? I have been using it for over a year and concluded that the reported distance is overstated by approximately 10%. The same issue was observed when using just the internal GPS and no changed after I added Garmin's speed sensor.

Is anyone else seeing the same?

0 YMDP over 4 years ago

Hello,
I also use it for mountain biking and my route measurements are correct.
it does not come from the mapping or from the reception of your gps?
I put GPS / GLONASS

0 rolfsg over 4 years ago

I see no general problem, at least as long as I use the MK1 under good GPS reception conditions. However, in mountain terrain with a restricted field of view to the sky and even worse in forests my MK1 suffered very regular GPS reception dropouts and the recordings have typically been inaccurate. Changing between, GPS+Galileo or GLONASS didn't make a difference. Also, there is an altitude calibration issue with the MK1 we discussed here for skiing, but it's also impacting mountain-biking. That's why I have given up on the MK1 for mountain sports.

0 MarcinB over 4 years ago

So today I did a ride using concurrently TWO devices: Descent MK1 AND Edge 530. And my suspicion has been confirmed, the Descent MK1 is overstating the distance by about 10%. See attached images. So for a year my distance while using the Garmin Descent MK1 was exaggerated by 10%, can't trust the Descent MK1 anymore for any sports I do!

Garmin Edge 530

Garmin Descent MK1

0 trux over 4 years ago in reply to MarcinB

Just a question: why do you believe the Edge has the distance right, while MK1 is wrong, and not vice versa? Did you verify it by riding some precisely measured distance, for example? Edge possibly displays the distance measured by the wheel sensors (if you use them), and that may be easily incorrectly calibrated. Or it is possible that one device uses "Smart Recording", while the other one uses "Every Second Recording" in GPS settings, or one with GPS, and the other one with GPS+GLONAS or Gallileo. Or that one uses 3D distance, while the other one measures the distance just flat. All of that can be adjusted in the settings.