RESISTANCE VERY HEAVY.

How many gears are on your cassette this will affect the number of spacers you require, if you have a 105 cassette you may need an extra spacer. These spacers need to be the correct thickness to make sure it is the correct pull on the system. 
if you remove the bike does the cassette move backwards easily by hand but more importantly does it wobble !!!

once you have the correct spacers relative to your cassette you have to make sure your gear indexing is correct you can find information on spacers on the internet along with info for the105 cassette as it wasn’t in the original Tacx setup documents 

as you seem to have the same problem with a new device it’s potentially something local so worth verifying the above and nothing is over tightened 

once you have ascertained the above is fine connect the Tacx to the training app and under settings training settings look for the grade slider is it set to 100% try moving it to 50%

under device manager do a device reset, followed by a calibration, try a couple of resets to make sure it takes

all of the above is based on my own experience when I didn’t use mine for 3 years it’s now working fine

Thanks already for the feedback.   With the extra spacer on the 105 my problem 1 was fixed. Now he works fine when the electric cabble is not used.  Problem 2 : heavy resistance after 5 seconds when connected  still going on. Moving the grade Slider to 50% has no reaction. Also several device reset followed by a calibration  has no positive reaction for the moment.

Looks like no resolutions offered here on this except for someone who "bought a Wahoo Kickr" ?

I have the same problem with a Tacx Flow but only when controlled by my Garmin 530, all rides are very heavy resistance with low 20s kph a real struggle even at zero grade. But if I use the Tacx Trainer App it is easy to get to 35kph+ at zero grade.

A related issue is that with the Garmin controlling the trainer all negative grades seem to be treated as if zero (ie the same heavy resistance) whereas with the App controlling the speed gets up to 40-45+ and while I don't expect negative resistance it does seem a little easier with the app controlling.

Tests with both using the same course will record similar cadence & power but very different resultant speeds. All tests preceded by a Trainer calibration using the App.

Any guidance welcome, thanks

Same issue New Flux 2 , have tried different apps Trainer road /TACX/Zwift & different OS , dosent work , rides are to tough to Enjoy !

Hey Sven, ik heb het zelfde probleem. Kunnen wij even contacten? Of heb jij de oplossing zo ook niet?

Hi stuur me even je gsm nr [email protected] dan nemen we contact mvg

As others have said I find the resistance on my Tacx Flux 2 extremely heavy, even when setting the Gradient to ZERO and does not appear to be adjustable. Mention has been made by some to "carrying out a reset" on the trainer, but I have not been able to find out how to do this. Can anyone offer any help and has any one found a way to reduce the resistance.

This forum is on a Garmin page. Why hasnt a Garmin rep replied with a solution. This seems to be a very common problem of which I am also having.

I ride outdoors with a group but cant ride indoors with them as they are all all pushing 2.8 to 3.0 w/kg. I struggle to just push 1.7 on my Flux 2 on the flats and 2.1 in a climb. Garmin......what is the problem with the Flux 2? Can you assist.

Did you manage to sort this problem im asking my friends the same question