Pacer bots

Hi all, I have a question which has come about after I rode Alpe du Zwift today. I often click on people as they overtake me, often to give them a ride on, but also as I’m interested in their stats… Like what actual wattage they’re pushing and to see their HR, if they have a monitor. Today someone overtook me and appeared to be holding a constant wattage. I mean exactly 340 watts, for about a minute while I was shadowing. No one is that constant, so I sensed foul play, but went back to my ride. A minute later I noticed the w/kg for the rider had dropped, so I took another look, and now the power was stuck at 290 watts. Another minute or so later and it was fixed at 404 watts. In the end, and as I expected, this person took the KOM on the leaderboard… by 8 minutes. I wondered if they were using an e-bike, but someone mentioned Pacer Bots to me, which I’ve seen DC Rainmaker using in test environments. Could people in Zwift be using such bots somehow, which they can alter at the press of a button, in order to capture KOMs and post ridiculous times? Or could there be a legitimate explanation as to how this person was holding such fixed power levels?

My guess is that they were using ERG mode.

This is not cheating.

I agree with Paul, 99% sure it is someone doing a workout using ERG mode.

One think to point out is that these people that do the tests using bots do it offline, so that they do not influence other riders by taking KOM or sprint jerseys.  

Look at their name on the sidebar. Any time you see a small bar graph to the left of the name (circled in red above), it means they’re riding in workout mode (generally ERG mode). 


They can be in ERG mode on a different app and just look like they are on a free ride on Zwift.

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Good point, Paul.  I hadn’t considered that!


While it is likely they were just using ERG mode, if you should come across odd behavior from other riders in game, you can optionally flag them so that our team can look into their performance. The article below should show you how:–How-do-I-flag-another-rider-and-what-does-it-do- 

Thank you for not including the rider’s username in the forum post. If you should miss the chance to flag the rider, you can also share their username with us directly by submitting a ticket to us that includes a brief description of the experience.

Thanks David. And while I’m fully aware what ERG mode is, I still don’t see how anyone can maintain an exact wattage for a whole minute… Surely it’d still fluctuate slightly. Unless some trainers do show a static value. The rider was doing a workout though, I did notice that. But anyway, appreciate all the input.

The wahoo kickr has an option of erg mode ‘power smoothing’ which will report an almost perfectly uniform power output.