Support for Tacx older smart trainers

(paha SBG [ZHU]) #61

That’s really good news John, thank you.  With this code we can test if it works with other trainers like Fortius for example.

One more question: is it possible with any ANT+ dongle to send ANT+ data or do we need a special one? 

Thank you.

(John Taylor) #62

Tested and working with both normal Garmin and Suunto dongles

(Maciek Matys) #63

Can we also test it? Thanks 

(John Taylor) #64

Testers required!

The following python script will simulate an FE-C Smart trainer to Zwift. Can someone test it with their ANT+ dongle on a Linux box

Instructions (for Ubuntu or Debian):

  1. Install pyusb: sudo apt-get install python-serial
  2. get script: wget
  3. run with sudo python

Zwift should find the Smart trainer when starting up and be set to a cadence of 90 with power 280W. Resistance levels will be echoed to console. No cheating on Zwift!

Please report issues on the github page:

Once I’m happy with this I’ll hook it up to the USB interface with the Tacx trainer and let you all know. I’ve only got an iFlow so obv that’s the first!- what other models do we need to be looking at? Let me know and I’ll start with the most common

Eventually we’ll try to wrap this up in a Windows exe and it’ll be run with a second dongle on the same PC Zwift is running on

(paha SBG [ZHU]) #65

Thanks John. I will test it next week with my Tacx Fortius and some Ubuntu. I will give feedback on GitHub, ok? Thanks once again.

(Robert Klinkhammer[TriFury]) #66

I can test on Mac if you want…

(Robert Klinkhammer[TriFury]) #67

I meant on an Edison or Pi…


(John Taylor) #68

I now have a working windows exe for trainers with the 1932 controller. If you would like support for the fortius with the 1942 controller please volunteer now so I can work out the resistance values sent and received so zwift can control the trainer and display virtual power

(paha SBG [ZHU]) #69

Thx John, as I have said I will try it this week with Fortius and send you what I see. If you need something special just tell me.

(John Taylor) #70

Thanks Peter- could you email me on and we’ll work it out

(Ha Waltie) #71

Does this also work for an TACX Grand Excel with the Tacx upgradeset T1925?

(Jo-) #72

This all seems very interesting to a Not-So-Smart Fortius owner. So let me ask this of you Cyclocoders, will a mere mortal like me with pretty good computer skills be able to implement this fantastic solution to buying a SmartTrainer? Because if i dont have to drop around a Grand on something new, I’d be a pretty happy guy. 

(John Taylor) #73

I only have a 1932 so would need to work with you to make other models work but, yes, there’s no reason why it shouldn’t work

(John Taylor) #74

In fact the T1925 is the I flow- with 1932 head unit. It should work straight off

(Kjetil Kirkholt) #75

Joe, its going to be very easy. You might need to change the driver for your trainer and you need to install some ANT+ dongles. Its ends up being a program on you pc that needs to be started before Zwift is started, no other hardware(except ANT dongles) . I have the system up and running using my flow trainer. John has done a fantastic job implementing this!!!

(John Taylor) #76

I’m happy to release the first working version of tacx-interface. It’s a Windows / Linux application that will connect to your Tacx USB trainer and broadcast as ANT+ power, cadence, heart rate. At the moment it is confirmed working with the 1932 head unit:

The project is at :

Please either download the python scripts, or the Windows exe

However I’d seriously recommend browsing the readme first as this will give you all the instructions on how to make sure you get the right one and how to use it.

No doubt issues will be found that’ll need fixing. Every time I release a new version I will post to this thread.

Add support for older 1942 head unit



(paha SBG [ZHU]) #77

Thank you so much John for this fantastic project. It is really a great job. This winter season on the trainer will be definitely better thanks to you. :slight_smile:

(Kjetil Kirkholt) #78

If anyone of you have a Tacx flow and a powertap i would really appreciate if you could make a power curve of the flow so this can be added in the software for better power and speed estimates.

(Dave Miller) #79

John, this is great!  I have a Tacx I-Magic, but pulled the trigger on a Smart Trainer last year.  Now I can hook my old Tacx Trainer back up and ride with my friend or spouse.

If I uninstall the original device driver, will this impact using Tacx TTS and Netathlon software which now works with the old trainer?


(John Taylor) #80

So long as the trainer has a different USB hardware ID you should be fine :slight_smile: on another note Kjetil has done some sterling work adding a GUI so a new build should be going up today