A few thoughts on the STAC Zero Halcyon



Hey everyone,
I was lucky enough to win a new Halcyon trainer and have been putting it through a variety of workouts to test its functionality and compare it to my kicker.

  1. It really is SILENT! My fan and singing are the only things that my wife–bless her heart–can hear now.

  2. It is much easier to set up than the gen 1 and the auto calibration of the magnetic arms is great. Be sure to get the wheel centered though! You can do this through their app and initial set up.

  3. if you have a power meter already on your bike (I have the Quarq and the Powertap P1 pedals) be sure to calibrate the trainer to that by seeing the average difference between the two meters and then going through their app settings. Erg mode is pretty bad with power match BUT when you calibrate the trainer to your power meter and then do erg mode, it works much better.

  4. Resistance mode right now is my favorite mode hands down but I am already biased here. I am still testing Erg out with the new calibration at higher intensities.

If you have any questions or want me to do any tests, let me know :slight_smile:


I’ve got one too. Since my home office (where I put my trainer) is next to my daughter’s bedroom and I do most of my training while she’s asleep, I’m really happy with the silence.

I have done the same thing with power calibration, and like you I don’t bother with power match because I can trust the trainer’s reported power. Since you have to install the freewheel weights in your wheel, I’ve got a dedicated trainer wheel so I’m not constantly adding / removing the weights, and I set it up with a single speed cog:
Of course that necessitates using Erg mode, but as a triathlete I don’t do a lot of sprint work where that would make much difference.


Great points!

I actually do not use the wheel weights because they did not add that much of a difference. I also like being able to just take the bike off and ride without swapping out wheels.


Which gears do you use for Erg mode. I’m on a 1x bike and running 42 x 12 and I’m less than impressed with the inertia (both sets of wheel weights are fitted) and “road feel” Maybe I’ve been spoilt by my KK Rock & Roll with the heavier flywheel. Would swapping my 42 for a 50 make any difference do you think?Also whats it like pairing your phone to the trainer using their app.? Again my experience is less than brilliant. Sometimes it works OK, other times I have to keep switching bluetooth on and off until it works.


I prefer the 53/17 or 53/19 gear for erg mode. I find that is the smoothest gearing combo while in erg mode. During resistance mode 60% is a good setting for a variety of cadences.

As far as the app, I connect it before each workout just to be sure the arms are the perfect distance apart from the wheel. As long as all other devices with TR or Rouvy or some sort of bluetooth connectivity are not operating then I am fine connecting.

It is certainly not the same as direct drive but compared to wheel on, it is so much better in my experience thus far.


I’m running 50 x 16, I think? I got a cheap wheel to be my trainer wheel (so I’m not installing / removing weights) and a single speed ‘cassette’ that has 16 teeth, I think. I dunno about ‘road feel,’ as long as I have enough inertia that I don’t feel peaks and troughs in resistance it doesn’t matter because I’m constantly pedaling anyway.

The STAC Zero app on my phone is terrible, and crashes a lot. I don’t have a lot of use for it, thankfully.


Their support sent me this link if it’s any help