Delayed / wrong correlation between map slope nad resistance

[jeerry]

Hi,

My setup: Tacx Neo 2T, Windows 10 with Tacx Desktop App 1.17.5.0, trainer firmware 0.0.37 (all latest available).

I started using the trainer 3 days ago. Day 1 and 2 - perfect. Day 3 (today) - no more correlation between map slope nad resistance. Slope 8%, light resistance. Slope -4%, hard resistance. Resistance changes "randomly", looks like its delayed by a few minutes or from another track.

What I dod so far:
- restarted PC, Tacx
- uninstalled TDA, reinstalled
- tried on the same track it used to work fine before (Canal du Midi, Barcelona city trip etc)
- verfied updates of app / firmware
- tested trainer on Tacx Utility, works fine.

No sucess, problem persists.

I also tested on iOS app - no problem, works as expected, resistance is delayed by a few seconds max. Looks like a sudden problem with TDA. Any ideas?

I contacted Garmin support as well, waiting for an answer.

[mcorn]

You have done the things I would have suggested. Have not tried my Neo2T today to see if anything has changed (I would be surprised if it had).

Not sure if you have tried creating a simple slope workout in the Select Workout page of TDA so you could do a non-video test. There is also a Tacx Ramp Test in Tests you could try.

[jeerry]

Thanks for the suggestion. I did not try the ramp tests before so I am not sure if this behaviour is correct or not.

1. Started from 100W, pedalling was fairly easy, I was producing around 100W.
2. Then aroound 1:30 into the test the resistance became much lower and even with 80 RPM on my highest gear I was not able to produce more than 100W.
3. The treshold changed after 2:00 but I did not feel any change in resistance.
4. The treshold changed again after 4 minutes but again, still very light resistance only, so I abandoned the test.

On a side note - while riding today there were moments (not correlated in any direct way to resistance problems) when I lost onnectivity and had to wait for the trainer wheel to stop and to restart pedalling to reestablish the connection - I don;t want to mix issues, have not tried deeper troubleshooting of Bluetooth yet except for the simple canonical steps, just mentioning this in case there is a relation between those two issues.

I also tested the custom slope - great test idea. I created the following slope:

30 sec 0%
30 sec 5%
30 sec 0%
30 sec -5%

When riding it I did not feel any change untli 1:50 when the 5% kicked in with full force. WTF. I will do more tests to verify if I can find a pattern. I will also remove all extra sources of Bluetooth transmission from the room...

EDIT

This is fun. I created another, longer slope.

30 sec -2%
30 sec +2%
60 sec -2%
30 sec +2%
etc

When riding I saw the first change of resistance at the 1:50 mark and then it followed my test ride to the second. So it looks like my Tacx has a 1:50 delay in reaction to the map slope when riding on the desktop app - and works perfectly well with iOS app. Time to solve that mystery

[jeerry]

Looks like I found a solution (at least temporary). Garmin support asked for Tacx utility app screenshots, so I rerun it for all the tests and realised there is one option I did not try before - Factory Reset for the trainer. And suprise suprise, it worked (at least for now).

For future generations: the best step do diagnose the issue is to create a custom slope training with alternating slopes (like +2% / -2% a few times for 30 seconds each) and test it o more than one device. And the solution for the delay seems to be as simple as the factory reset of the device.

I will come back after a few days (or immediately if the problem comes back) to update on the long term results.

[hb99]

I had this problem occur randomly earlier this year on video rides that had at other times been fine. I never did a factory reset and the next time I rode a video all appeared normal.

Last week I was riding Tour of Majorca Stage 4 and had a really bad dose of the "slope delays". I worked out there was initially about a 2 or 3 minute delay to the resistance compared with the video and slope % displayed, but over time this steadily increased to probably 15 minutes making the final climb ridiculous - spinning in top gear at 90+rpm but generating about 20 watts and doing 1kph! The resistance still thought I was on the big previous descent. Next ride all was normal on a different course.

So it looks like one of those wonderful intermittent problems. One thing I haven't tried is stopping the ride, restart everything and try the same ride again. Next time!

Do others get this problem?

[mcorn]

I have not seen this problem. I always use downloaded videos rather than stream and have an Ethernet connetion. Are you streaming? If you are streaming, do you connect to the Internet by Wi-Fi or hardwire?

[hb99]

Apologies for the delay Michael. Have been out on the road in glorious sunshine I usually stream - certainly was on this one and use a wifi connection. The connection is very good with the router in the same room and we have the fastest fibre available (or so they say!) Minimal or no other traffic through the router. It is odd that the problem only occurs occasionally, but I wonder if it is at the server end.

[mcorn]

Apologies for the delay Michael. Have been out on the road in glorious sunshine I usually stream - certainly was on this one and use a wifi connection. The connection is very good with the router in the same room and we have the fastest fibre available (or so they say!) Minimal or no other traffic through the router. It is odd that the problem only occurs occasionally, but I wonder if it is at the server end.

Well, if the router is in the same room and you get this problem again, you could try running an Ethernet cable to the router to see if it makes any difference. You could also download one of the offending videos to see if running it that way made any difference. You could also try streaming at 720 rather than HD.

[Martin]

Same issue here, Today out of the blue resistance and slope not correlated anymore, restart/ tried several videos but no success , saved/streaming videos, excellent internet connection, calibrating. (The only thing that was changed is the Windows OS from 10 to 11)
iPhone Tacx app: working excellent (resistance and slope exactly right)

[Martin]

Installed the Tacx desktop app on a second computer with Windows 10, no problems. It seems Windows 11 is the source of this issue (for me, maybe also for others)

[hb99]

Re: Installed the Tacx desktop app on a second computer with Windows 10, no problems. It seems Windows 11 is the source of this issue (for me, maybe also for others)
Top

This is not the case for me as I am still on Windows 10 - will wait for others to iron out the issues that introduces!

[Cycling2011]

Last week I was riding Tour of Majorca Stage 4 and had a really bad dose of the "slope delays". I worked out there was initially about a 2 or 3 minute delay to the resistance compared with the video and slope % displayed, but over time this steadily increased to probably 15 minutes making the final climb ridiculous - spinning in top gear at 90+rpm but generating about 20 watts and doing 1kph! The resistance still thought I was on the big previous descent. Next ride all was normal on a different course.
Do others get this problem?

I remember staying on W7 because of a out of sync issue with W10 using TTS4.This did get fixed eventually.It could be that TDA has the same issue for some users after updating to W11.I will not be rushing to update to W11 on my TDA PC when W10 will still be supported until October 2025,

[Michael Velo]

I had what sounds like the same badly out of sync problem which was also accompanied by the gear slider not working at all. After calling Garmin tech support, I was told it was an issue for the Dutch since they write the software. I had installed Win11 thinking it might solve the issue (yes, really) and it just made things worse. I never heard back from Holland so I reinstalled Win10 and everything worked fine again with one exception. When I finish riding a filmed course, I'm shown the summary screen at the end with the cool down time at the top. When the I select the "save" option, the cool down screen disappears and is replaced by the home screen with the map and the listing of videos. I'm afraid to mess with this too much since everything else is working, but it would be nice to get the cool down screen back. Any ideas?