Bkool Pro odd behaviour during workouts only

When using the Bkool during a non-workout ride I’m getting what I would consider a realistic experience i.e. expected watts for a reasonable cadence and gear ratio. However when I try to use one of the workouts (FTP Builder) the Bkool seems to be out of calibration and the resistance is all over the place and seems to be reading very high power for very little actual power input. As a result I’m finding it very hard to maintain the target power rating without going over. I end up pedalling at a very low cadence to try and keep the power reading at the desired level, 120 watts for instance. This just seems to happen in workout mode. Anyone had a similar experience?

I had that same issue tonight. I also noticed on my Garmin it said I had gone 2.2 miles but on Zwift it said 5.6. But I agree with the FTP. I was having to pedal at a cadence of about 15 in order for it to not go over the watt threshold for each required metric in the FTP Workout. I thought my calibration was off or that the BKOOL was not working in sync with Zwift. I would love to know more about this. I switched over to the BKOOL simulator to see if something was wrong and the speed on the sim was matching my Garmin as well as the correct distance. 

Yeah sounds like exactly the same issue Stephen. No one from Zwift able to comment?

I use a bkool pro with a power tap G3 hub and don’t get the issue you have so it must be how they are handling the power feedback from the bkool.

The only issue I have is, rarely, I will suddenly get full load on the book for about 5 seconds then all is OK

Experiencing he same exact issue win my bkool and it is such a buzz kill as I really want to use the workouts!

Scott, I’ve raised a separate ticket on this issue and have received confirmation from tech support that they will be investigating the issue but are very busy at the moment. I agree it’s frustrating and means workouts are just not an option for me at the moment.

Me too with Bkool. Difficult to control during normal riding as well. Something has changed since the last update

For me it’s just the same with the Bkool Smart Pro. In “Just Ride”-Mode everthing works fine, but in Workout-Mode the resistance is much to hard, so you only can pedalling in low cadences e.g. 30 rpm in lowest gear. It’s very frustrating! 


It might be worth raising a ticket with tech support like I did. I’ve still had no response back from Zwift acknowledging there is a problem. All I’ve heard is that they are very busy and will look into it.

Response back from tech support:

Hi Stuart,

The Bkool ERG mode issue is a known firmware issue with the Bkool Trainer. Both Trainer Road and Zwift are working with Bkool to identify the issue and will test their new firmware when it is released to us.

Unfortunately we cannot give a better update until we hear from them.

Eric C.
Community Support Manager

I have found that simply toggling “ERG” mode off for training rides solves the problem.  Given the workouts are power output focused, it really doesn’t matter much to me.



Thanks for that, it worked for me, and was able to complete my first workout.

Not sure what I’m missing by having ERG turned off.

All we are missing is the simulated grade resistance.  No big whoop for training rides. 

Ah right. Yeah I did notice that the simulated resistance remained constant throughout the lap.

Thanks again.



any update? I have the same issue in workout mode. Bkool Pro… It is very strange…