Cycling slow in the Zwift world


I bought a Tacx Flux 2 smart indoor trainer. When cycling in the Zwift world I would be pedaling on the trainer at a decent pace yet in the world I am going really slow.

How can this be corrected so it works hand in hand?

Hi @Deon_Petersen, welcome to the forums.

Please give us more details about your setup. What devices do you use to run zwift, how do you connect (bluetooth or ant+), what type of cassette did you put on the trainer, what bike is on the trainer (what gear ratio), etc… the more details the better and we will try to assist.


Hi, thank you

I connect via bluetooth. I am using a shimano 105 28 cassette on the trainer. My bike on the trainer is a Trek Emonda sl6 disc.

I hope this helps

That should work fine. Double check that you entered your height and weight correctly (if metric in kgs not lbs for example). What route are you on, is it a hill that is slowing you down?

Also, have a look at how your speed is determined.


That is all correct. It is on a flat service. The top bar above when show you doing maybe 15kmp yet I am possibly doing double that on the actual trainer, so catching up with anyone on the road is almost impossible.

Ignore the speed that your trainer is reporting, speed within Zwift is based on power/watts and the other variables in the link above…

Make sure you calibrate the trainer using the Tacx app.

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Thanks Paul - I have calibrate the trainer in the Tacx app already.

I saw Zwift also has the calibrate yet when I ride to 37km’s then it tells me to keep that speed, then no other notification comes up further than that.

Are you using a trainer tire?

Nope, this is the Flux 2 so the rear wheel goes onto the cassette on the trainer. My rear wheel comes off completely

OK, how many watts are being reported when riding, that is what will determine your in-game speed.

ie. 200watts I was just on the trainer for 15min to check

What in-game bike did you use.

Please read the link that @Mike_Rowe1 posted also, it explains in-game speed.


Just a free ride. I have read he’s post, it makes sense. I will give it another try or send you a screenshot of what I am seeing