Elevation WRONG!! Wheel calculation WRONG!!... still didn't get fixed
PlannedI have a bittersweet taste with my karoo2. As first adopter I know that it would get some time to adjust and fine tune the device, as a developer I know what that means. But after some time, I expected to get some functions at least as precise as other brands (won't say garmxxxx... but it was expected to be the "garmxxx killer"....).
The device itself is great, good quality, great screen, responsiveness is far better than other brands, but.... software is improving funtions, adding more and more data on screen, segments, climb information, phone notifications... all are great and I think very well implemented on UI. All these is blinded in my opinion with an awfull precission, I will explain myself:
Elevation gain and gradient: totally wrong, don't care the route, don't care you adjust manually on every ride. This is one sample ride (this happens on every each ride), I had battery problems with my first karoo2 unit, support team changed it for a new one, same problems with this. So this is not a device problem, barometer calibration... it seems a software calculation or map dem problems. This is the same ride without and with strava corrections
+100 mts overestimation!! no mather the device, no mather the ride, no mather you adjust elevation manually... this happens every ride, more kms more elevation deviation. Climber function overestimates the average gradient, you can see some times a 13% degree average on a segment and the live gradient shows a maximum of 7%, so it is impossible to have an average of 13% with a max of 7%...
Speed and distance: I have a garmin wireless sensor. This is a first day issue too and it is not fixed at this time. Only fix is set wheel manually. Ok, but it is supossed to have this preciselly calculated by the device, using gps and data from the sensor... I can't understand why this is not working whell. Haven't got this issue on other gps units I used, the are very very precise. I know strava will have his percentage of error, garmin its own, no 100% perfect, but at least a very accurate calculation was expected for a device like this. I ended all rides having more kms, mor speed like the one showed before (the below image shows same ride with strava correction using gps data)
I know you all are supposed to be working on putting more and more functionality on the device, that is great, but this issues, I think are in my opinion, much more important to trust a bike computer, this are basic things that do a bike computer a serious training device or not.
Please, fix this first before changing more and more things.
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I’m not sure you should be trusting comparisons with other devices or Strava’s corrected elevations. I’ve found elevations to be notoriously inaccurate whatever I’ve been using. For instance, my wife and I would do identical rides together, both using Wahoo Elemnt Bolts, and never have distances or elevations been the same - often not even close.
Also, I just tried “correcting” elevation data on Strava for a ride recorded using the K2 and another recorded using the Wahoo. Both were corrected by 100-200 feet. Strava rely on their base maps for elevation as far as I know. GPS data is known for being less than 100% accurate. My friend has a Garmin watch and some rides we do together do not even show that he rode with me!
As for Climber, it wouldn’t surprise me if the issue has a similar root cause. I don’t worry about the absolute numbers and am happy seeing the overview of what is ahead of me rather than fretting about the average gradient over the next 50 yards - some of them do look wrong for sure!
I wouldn’t go worrying too much about this stuff.
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The wheel calibration has been a know issue for some time. It's really disappointing this hasn't been fixed yet. While I appreciate the new features, there should be an "all hands on deck" effort to fix the wheel sensor calibration.
As to the altitude, I don't know who to believe. Metrics are all over the place when I ride with other people.
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@Edgar Karel - it's not fixed for me, unfortunately. I used auto-calibration yesterday and the Karoo clocked my 64.36 mile ride at 62.39 miles. I didn't look to see what it had calculated for the wheel circumference vs. my manually measured 2123mm. This is using a Powertap G3 as the speed sensor.
No issue with elevation though, that seems fine.
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Yes, and the planned distance on RideWithGPS was also ~64.4. You can see the ride here: https://www.strava.com/activities/6023635852 and the planned route here: https://ridewithgps.com/routes/37638103 . I took a wrong turn that added about .5 miles.
I just checked the Karoo and it calculated the wheel circumference as 2027mm, which is obviously low. I measured my 700x25c tires at 2113mm unweighted, so the true value with me on the bike is likely a bit lower than that. The "normal" value for 25c tires is 2105mm.
Based on the distance error after Strava correction, the true value is likely somewhere in the neighborhood of 2027 * 64.36/62.39 = 2091mm.
I'll try the auto-calculation again next time I ride and see if it does any better - my understanding is the Karoo recalculates the circumference near the beginning of every ride. If it's still wrong I'll just set a manual value and call it a day.
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