Race 2 accuracy
-
@isaac.net said in Race 2 accuracy:
@jjpaz said in Race 2 accuracy:
@isaac.net said in Race 2 accuracy:
Hi,
I’ve done a new comparison, this time of an old running activity. The activity on Sports-tracker shows a distance of 9.52km, and the GPS points of the route are almost perfect. I marked the same route with an online distance calculator (https://www.calcmaps.com/), and the result was 9.67km, practically exactly the 1.5% difference mentioned in the thread.Here are the screenshots:
If, in your SportTracker activity, you open the “graphs” menu, you can show activity information over the map. If you move to the right (end of the activity) maybe you could see a final distance close to the 9,67km (the “Raw” measured distance).
Yes, that’s right, in that case the distance it shows is 9.65 km. It’s clear that Race 2 correctly captures the GPS points but then processes them incorrectly. In my opinion, this should be a priority bug fix.
I don’t know if it process de GPS data incorrectly, for sure it does it in a different way in comparison to other models.
-
@jjpaz what I posted are raw data from JSON files in quantified self. One of the watch recordings is no longer in the Sunnto database. I believe 3% is the acceptable GPS error for handheld devices.
Vector/T6c/Vertical 2 Ti
-
@Brad_Olwin I think that is valid for GPS but not for GNSS dual band devices (and even more when It seems something strange is happening with the Race 2 but not the others). Someone correct me, if I’m wrong.
-
@Brad_Olwin In my opinion, an error of more than 1.2km in a marathon (3% of 42km) is unacceptable under any circumstances, especially if all other devices measure close to the actual target (even the cheaper ones). Especially considering that the position values recorded by the watch are very precise
-
I think while the actual position data of a point may have some error, the distance measurement by GNSS is quite precise these days. Also some filtering occurs to the data measured every second.
What we see is, that under some circumstances Rce 2 measures short, while this is not always the case (see John Korir’s Marathon distance in the other thread).
As this is not a special setup only in Race 2, there is not much to do about it. If it does not happen everywhere and every time, this is just an arbitrary deviation with the range of 0.5%.
Not sure what else to add to this thread now. -
@Egika Are you sure it only happens in certain circumstances? Since I became aware of the problem and started checking distances, all my routes have the wrong distance. Today, a run of 6.01km according to Race 2, after correcting the distance with Strava, was 6.10km. Again, that 1%-1.5% less distance…
The difference can also be seen in the graph of sports tracker, 6.01km in activity info vs 6.11km in the graph -
@Egika Yes, unfortunately it looks like we’ve come to the end of the road and Race 2 users are just going to have to live with it
-
@isaac.net maybe your individual device is a little different. We have seen a tendency but we have also seen perfect matches.
-
@Egika I’ve worked in software development for a long time, and with the correct track data, the solution is possible, since it’s not a precision problem but a distance calculation issue (software), as demonstrated on the Sports Tracker website. In the same activity, you can see the distance calculated by Race 2 and by the app on the graph. It’s a 100% software problem and therefore solvable. If the problem is due to processing, could it be that the routes with less error are straighter, while those with more error have more turns? I’ll try a completely straight route in the next few days to see what happens…
-
@isaac.net sorry, you are on the wrong track.
While probably everything might theoretically be solvable by software, I doubt that Suunto is going to invest a lot into this one. But who knows…t6, S6, Elementum Terra, Ambit 3 Sapphire, Spartan Ultra Copper, Traverse Alpha, S7 Graphite LE, S9B Ambassador, S9P Titanium, S9PP Titanium, Vertical All Black, Race Titanium Charcoal, Race S Titanium Courtney, Run Lime, Race 2, Vertical 2 Titanium
-
@Brad_Olwin said in Race 2 accuracy:
@jjpaz what I posted are raw data from JSON files in quantified self. One of the watch recordings is no longer in the Sunnto database. I believe 3% is the acceptable GPS error for handheld devices.
When I upload Suunto JSON files in QuantifiedSelf the distance showed is the same as summary distance saved the FIT file, not corresponding to the gps raw data distance.
If you want (and have time) you can compare a short activity wearing Race 2 and another watch and repeat the test.Maybe our expectations regarding accuracy in Race 2 where higher, moreover comparing with other watches. In my case I combine Vertical and Race 2 in my trainings and I know that I have to apply a “mental calibration” when I compare data with both watches, and that’s all. In general I’m happy with Race 2, despite its behavior is very reliable when I repeat circuits.
Thanks for your contribution.
-
I’ve got about 1 week left of my return window…I’ve already sent one back as I wondered whether it only affected certain units and hoped I might be lucky second time round. I was also banking on it being addressed in the update…to me the accuracy fix would’ve been better than all the new features that came along. Might be time to try a Vertical 2…
-
Hello,
On the 24th, I conducted some tests, first on a practically straight route, and then on a route in the same area with hills and curves. My hypothesis that the Race 2 is incorrectly processing the recorded points was confirmed. The straight route is marked every 500 meters; it was 4.04 km according to the Race 2 and 4.05 km according to the track, measuring almost exactly during the activity. During the activity with curves, the problem returned, subtracting 80 meters from the total: 4.00 km according to the Race 2 and 4.08 km according to the track.I’ve attached some screenshots that I will send to Suunto support:
I encourage you to conduct these tests and also send them to Suunto (support@suunto.com). It’s the only way they’ll take the issue seriously. If this problem is widely known, I doubt Suunto will sell another Race 2 at its current price.
Regards.
-
-
There’s an user in reddit u/slimak131 that wrote a program to evaluate the quality of a looped track. It seems pretty intesting for testings. I’m posting here the info
Source: https://www.reddit.com/r/amazfit/comments/1thef8o/amazfit_cheetah_2_pro_vs_garmin_forerunner_970/
Links:
-
Super interesting thread!
I guess that is the curse of a consumer device. On one side we have a lot people shouting loudly that they ran marathon and their watch counted 42,66 kms and on the other side we have geeks and purists like us trying to get as raw number as we can get. And Suunto have to find a balance between all. Haven’t used my Race 2 for marathon or HM so cannot tell, but I assume it shows closer number to actual distance. I wonder if that is the reason for this behavior. -
@aiv4r in my opinion, It doesn’t seem to be the problem with Race 2; point capture is very good. You only need to look at the track generated by the captured points. In terms of repeatability, I think Race 2 does very well. The problem arises later, during post-processing of the collected points. That’s when Race 2 shortens the distance, and by shortening the distance, I mean that on a course with turns of a known distance, Race 2 makes some kind of cut, showing a distance shorter than the real distance and also shorter than the track saved by the device itself.
-
said in Race 2 accuracy:
Hello,
On the 24th, I conducted some tests, first on a practically straight route, and then on a route in the same area with hills and curves. My hypothesis that the Race 2 is incorrectly processing the recorded points was confirmed. The straight route is marked every 500 meters; it was 4.04 km according to the Race 2 and 4.05 km according to the track, measuring almost exactly during the activity. During the activity with curves, the problem returned, subtracting 80 meters from the total: 4.00 km according to the Race 2 and 4.08 km according to the track.I’ve attached some screenshots that I will send to Suunto support:
I encourage you to conduct these tests and also send them to Suunto (support@suunto.com). It’s the only way they’ll take the issue seriously. If this problem is widely known, I doubt Suunto will sell another Race 2 at its current price.
Regards.
I used the program with the track with curves that I uploaded in a previous post (removing the final section that was off the track). It confirms my suspicion that Race 2 doesn’t have accuracy problems in data capture; it’s an error in processing (software).
Only 1.51m of drift on the 2-lap circuit with curves, asphalt, and clear skies:
Gemini Smart Track Drift v23 ---------> START
Autonomous Mode (Method 1). Treatment: 2026-04-24_curvo.gpx…**REPORT FOR: 2026-04-24_curvo.gpx (METHOD 1)
Parameters: 3 min / 40 m
Total distance: 3698.0 m
Comparison distance: 3698.0 m
Number of samples: 1067AVERAGE DRIFT: 1.51 m**
-
Hello,
I can confirm my R2 shows always a litte shorter distance than my Ambit 3 (about 1%). This is not a tragedy but a software fix would be appreciated -
@isaac.net I get that
was just wondering if Suunto added artificial cut of distance for masses, that usually run more than actual race distance. (mostly road, since trail folks usually do not care that much about ±400meters).
