I have been riding for many years, not competitively but for fitness purposes and enjoying the freedom of cycling.
I do both road and off-road but mostly road (most of my offroad with my 4wd
)I recently purchased a Polar M460 with HRM as I have been using Polar from day one and had been satisfied with HRM accuracy.
I have a query for the general forum members as it is somewhat technical.
Cut to the chase, the Altitude measurement of the unit is not consistent even though I calibrated it before I left home and sometimes halfway through the ride (say after 2 hours) to known topographic map heights using the contour lines.
Polar told me that the unit has +/- 20m accuracy and the barometer can be thrown out by changes to atmospheric conditions.
The 20m accuracy I think it is a furphy, this accuracy exists only if you use the GPS on its own.
Does anyone here have the expertise in this field, that will be helpful?
By the way, I often get consistent results and noticed it happens when it is cold.
When not measuring accurately the error is around 8% which is ok I guess for low altitudes.
Today here in Melbourne the temperature is around 20 C and on my return back home, the elevation was around 9% higher.
Cheers and thanks in advance.
