Garmin Connect Max Speed :-/?

[HLaB]

Does anybody else get wild readings on GC max speeds ? The chart looks consistent'ish with RWGPS and Strava (circa 33mph) but the summarised max speed is way out at nearly 49mph I certainly never reached that in the wet

 

[Gary E]

I've been quite impressed with it TBH. In fact my one disappointment was when both my Garmin Edge 800 and my Cateye Strada agreed that I'd reached 55.5 mph but for some reason GC recorded my top speed as 54 mph

 

[T.M.H.N.E.T]

Mine fluctuates but it's not to the extent of 16mph! (spd/cad sensor paired)

Same ride.
Strava Max: 24.7mph Strava Avg:16.9
GC Max: 26.8mph GC Avg:17.1

HR does the same.
Strava Avg: 146bpm Strava max: 171bpm
GC Avg: 146bpm GC Max: 172bpm

Cadence is equal :O Both average of 83

 

[Rob3rt]

Strava uses GPS data.

Garmin Connect uses the GSC10 data if present. So if you happen to stop with the magnet in just the right place, or some otherwise similar circumstance, you can get some odd max figures recorded where it is triggering repeatedly from minor movements.

Strava vs GC average speeds always differ.

Cadence should be the same as it comes from the same sensor, so within rounding errors, they should match. Same for HR.

The plots on Strava and GC are plotted to a limited time resolution, thus the spike may not show up. For example, my power data on GC or Strava may show 4-5 drops in power (a bug with the 810 causes the power values recorded to drop to half of the current power for 2-4 seconds periodically - Garmin are working on a solution) but Golden Cheetah or WKO+ will show many power drops, up to 30+ for the same duration of time, due to the greater time resolution on the plots. They are present in all data (as will your speed spike), it is just a graphical limitation on Strava and GC.

 

[T.M.H.N.E.T]

Interestingly Rob. The ride above was done with GPS off so there shouldn't have been fluctuation as it was all sensor data

 

[Rob3rt]

On the turbo? That is slightly odd, but then again Strava use their own algorithms so there may be a difference in the way it computes the solutions, they possibly also have different rounding limits, Nigel (400bhp) mentioned something about how the way Strava deals with moving and elapsed time may differ from Garmin Connect. I am not certain re this. Not sure about the max values. Try looking at the data in training peaks or WKO+ and see what values that gives.

 

[T.M.H.N.E.T]

Yeah it was. I'll have a look in WKO

 

[HLaB]

It was done with no sensor and just gps

Edit: I should have looked earlier but Garmin Training Centre shows it at 32.6mph, fairly consistent with Strava and RWGPS too. The random fluctuation just seems to be cropping up in Garmin Connect; it makes me lose all faith in the GC product

 

[T.M.H.N.E.T]

@Rob3rt

Golden Cheetah: Agrees with Strava on HR avg/max but avg speed as 17.2 no max

TP: Ties up with Garmin Connect on all numbers

All uploads taken from the same file directly off my 800. Must be a little inherent fluctuation :O

 

[BJH]

I have a speed recorded on my Garmin at 1000 mph

I am also reasonably confident that I have not ridden that speed, or been in a car or an aeroplane that could have managed it either.

I suspect Iwould have slowed at the point when the sonic boom went off !,,

 

[Rob3rt]

I have a speed recorded on my Garmin at 1000 mph

I am also reasonably confident that I have not ridden that speed, or been in a car or an aeroplane that could have managed it either.

I suspect Iwould have slowed at the point when the sonic boom went off !,,

GPS glitch of some sort, not the same issue this thread relates to, the issue here is different metrics being computed from the same data.

 

[srw]

It was done with no sensor and just gps

Edit: I should have looked earlier but Garmin Training Centre shows it at 32.6mph, fairly consistent with Strava and RWGPS too. The random fluctuation just seems to be cropping up in Garmin Connect; it makes me lose all faith in the GC product

Garmin Connect told me that I was running at something over 100mph the other day. I don't think I've ever got a reliable maximum speed out of a GPS unit - the measurement accuracy isn't good enough to tell the difference between standing still and moving a short distance very quickly.