Way too little resistance in event

Hi everyone,

During yesterdays Power Up Training Camp Workout #1: Climb, 21:20h CEST, I felt a significantly reduced resistance from my trainer (Tacx Genius Smart). In hardest gear, I was barely able to reach 250W whilst not surpassing cadence @85rpm. On top of that, the 250W felt like 150W.

When switching off ERG and setting easy incline, the trainer immediately gave me a pretty hefty resistance, and measured wattage doubled almost instantaneously.

Judging from the messages it seemed quite a number of other riders had similar issues. For me, it was the first time to experience this, I should add though that I am relatively new to Zwift so “Dumb user” could well be an answer in my case. :slight_smile:

Any idea what might have been going on here and what I could have done to avoid the situation?



Sorry Zwift wasn’t providing the best experience Andreas! Yes we have had a lot of resistance issue cases with various trainers, including some TacX trainers. Has this only happened one time and have you rode since with the game operating resistance normally?

Also have you tried troubleshooting ANT + possible dropout issues? https://support.zwift.com/en_us/my-ant+-signal-is-dropping-(cycling)-SJdW01bHX

Hi Vincent,

Thanks for caring! Yes, this was the first time this happened at the time of writing, but unfortunately now I had the same issues some two hours ago on Power Up Training Camp Workout #3: TT : spinning like mad in ERG-mode to yield only barley the required wattage, and the watts on the screen were way higher than what it felt like. This all in a 52-11 gear setting, max. I can do.

Around 1/3 into the event, I switched into incline mode and this immediately gave me the resistance needed. From all I can tell, the issue seems really be centered around ERG-mode.

I went through your guide on ANT+ related steps, none of them seems immediately pertinent to the issue. It also does not look like a protocol level issue, wattage in Zwift is shown constantly with frequent and (at least in relative terms) plausible changes. Plus, there is also no change in setup (both hardware and software) since I completed the Tour of Innsbruck with no issues - apart maybe from any automatic Zwift or Win10 updates. The machine is used only for Zwift and TTS4.

I will try to ride some hills tomorrow outside of a guided event setting. Any further suggestions will of course be highly appreciated. Even more appreciated will be, Vincent, if you confirm that it is my defective Genius Smart unit causing all of this, it will help me a lot in justifying the investment into a brand-new Kickr 2018 in front of my wife :smiley: .



I would love to help you out with new investments haha but what would help us would be the log file from the Power Up Training Camp workout. Can you send us a support conversation with the log files attached?

How to find log files: https://support.zwift.com/en_us/how-do-i-find-my-log-files-running--HkFCtXX8m
Support Conversation: https://support.zwift.com/hc/en-us/requests/new

Hi Andreas,

having the same issue here with a TacX Vortex Smart (power and cadence readings come from a Stages Powermeter and are correct). For a target wattage of 220W I’ve to peddle at least 105-110 rpm. HIT intervals are nearly impossible, as I’d have to go up to around 130-150 rpm!

Did you find a solution in the meantime?