Uphill Resistance Delay

Hi All, I’ve scanned the discussions for this topic and the latest post I could find was 2015, so I hope no one minds if I bring it up again.

I’ve been on Zwift for over a year but I recently upgraded to a smart trainer (Tacx Neo 2, firmware up to date). I’m loving it, but I’ve noticed there’s a pretty noticeable delay in the resistance ramping in when I hit the hills. I find that Zwift shows I’m on a grade for up to 5 seconds before my trainer responds and I feel it in the legs. On longer hills it’s not a big deal, but on the shorter rollers I find it can really throw me off, especially when I’m trying to work within a bunch of other riders.

Does this bug anyone else? Is there a setting I’m missing? Or is this normal?

I have noticed this as well. In general there seems to be a lag between changes in the environment being reflected in the trainer and vice versa. For example, the phone app reflects any increase in power output before the computer does.

I’d say it’s normal. I certainly have posted in the past about there being roughly a 4 second difference between what Zwift says and what my trainer seems to be emulating.

Even after several years I still don’t get why it’s like that. After all, all the communication is electromagnetic so moves at more or less the speed of light. I guess some of it is response time within the trainers themselves, but 4 seconds still seems slow to me, especially with something like a Neo where the resistance is also electromagnetic.

Eventually, you do get more used to it and learn to anticipate the changes more, as well as keeping on the power even when Zwift says the gradient has levelled off.

Thanks everyone! I’m happy to live with it, as long as I haven’t missed anything in the setup or done anything wrong.

Ride On!

If the delay is in the trainer and this is a common issue, you would think the Zwift could compensate by calculating an offset to account for trainer reaction delay.

I’d assume some look ahead/behind gradient averaging is necessary.
You don’t want to be sending instant data if there’s a mapping/network issue causing 0%-100%-0%-100% resistance changes.

I am currently suffering from an issue like this, however my lag is more like 30 seconds. Riding around new york the uphil parts I feel like I am on the flat, but towards the bottom of the downhill all of the reistance kids in. I have written an email to zwift support, but no response so far.
I am using latest firmware on tacx flux 2 and latest software on appleTv.

I know from experience that having an amazon echo as my appletv bluetooth speaker or anywhere near the trainer causes huge interference for me, so I have completely removed that, but still the issue exists. Makes riding almost impossible.

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I have the same issue with my tacx flux s, very big delay, have you solved your problem? Thanks

I’m no longer having the delay issue, though I can’t with certainty say why. I’ve done a series of Zwift, Windows and Tacx updates since having this issue, and improved my Ant+ connection (through reducing the distance to the sensor) and that’s cleared things up. Good luck!