Zwift Hub One Virtual Gears - Gear Indexing

Hello everyone,

The gearing of the virtual gears of the Zwift Hub One seem to be off.
The virtual shifting offers 24 gears. In irl it would be a 24 gear casette and not like e.g. a 2x12 which would have intergearing and result in less actual gears.
I usually ride between gear 14-18 on flats.
Today i rode up Alpe du Zwift in gear 16 at an relaxed 2W/kg which put me at speeds below 10km/h.

I assume this must have to something with my front chainring size of 30 (or 32?). The manual says to use the left most chain ring on 2x bikes. And the noise the Hub/chain makes when instead using the larger 46t confirms the 30t to be the right one :smiley: .

This leaves me with the following questions:

  • Can i somewhere reindex the virtual gears? Not every Zwift user will have 1x bike with 50t front chainring :smiley:
  • Are gears 1-13 just useless then? I mean at that rate gear 1 would allow me to pull a 4 ton EV to the car mechanic :smiley:
  • Why can I use same gears on flats and on climbs? Is there something “smart” happening in the software that im not aware of?

I believe my problem to be most likely a lack of understanding virtual shifting or not yet having seeing a setting option somewhere.
Does anyone else have similar problems with virtual shifting?

PS: I forgot to mention that im relatively new to Zwift (1 month) and have mostly ridden training programs in ERG mode so far.

I think the gear ratios are what they are. Some people with really low (physical) gearing use the QZ app as a pairing bridge (qzfitness.com). It can be used to increase base resistance with virtual gears. I do not know for certain that this would work (ie, it may interfere with the Zwift virtual gears) but maybe the developer @Roberto_Viola will know. It’s a paid app but he provides a lot of support and enhancements for people who run into problems. It has a lot of settings so you may need the help.

You could also possibly replace the 14t cog with a smaller one like 11t, but I’m not sure if this might increase chain rub on the plastic parts of the Zwift Cog. Those parts are technically optional and could be replaced with aluminum spacers, if you promise to never touch the rear shifter while riding.

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Another option would be to install a normal cassette on the trainer. The Cog is just a Hyperglide compatible cassette and you can take it off. Then you could shift into high gear and leave it there, and use virtual shifting from then on.

That doesn’t sound right that you are using the same gear on AdZ (at an easy pace) as you do on the flat.

Edit - hang on, was this in a workout on the Alpe? If so it makes sense because you don’t feel the gradient in a workout.

To test this you possibly need to ensure your Trainer Difficulty is set to 100% and then try out some steeper climbs than Alpe du Zwift, say The Radio Tower.

Thank you for all the replies.

@Paul_Southworth: Going third party feels weird. I would not need Zwifts virtual shifting at all if i would use 3rd party anyway. Additionally Zwift Hub One works without rear casette fully focused on virtual gears and a half-assed solution from Zwift would annoy me. That beeing said qzfitness would most likely be a working workaround. Thank for that!

@Steve_Hammatt: Oh think you put me on the right track, it was the “Tour of Fire & Ice” workout. But why would they remove the feel of gradient? Would that not just remove the immersive feeling given the vritual experience? But i think this is where the answer of Ian explains it for me :smiley:

@Ian_Attoe: I indeed had the trainer difficulty near the lower end. If i remember correctly i changed it because i thought i meant the trainer difficulty while not actively riding, e.g. in menu trainer difficulty.
I assume moving the slider to max will mostly mean “real” shifting experience? I will test it out later but i guess this will most likely fix my “issue”. Thank you.

What is the reasoning for that setting then? People do not want to shift as much?

If you could feel varying gradient in a workout then that’s going to make it a lot harder to maintain the constant power of the particular block of the workout tnat you’re on.

On a climb during a workout, althoufh you won’t feel the gradient in terms of resistance through the pedals, Zwift will still use the gradient when it calculates the speed based on your power output. So you’ll be going more slowly in a workout up Alpe du Zwift, for example, than on a flat route like Tempus Fugit.

Trainer Difficulty scales the gradient of climbs and descents in terms of the resistance sent to the trainer. It does not directly affect speed in the game which comes from your power output. What you can expect is that higher Trainer Difficulty will increase resistance when you’re going up hill, decrease resistance when you’re going downhill (so you will spin out more easily on descents), and it will do nothing on flat terrain because scaling a 0% gradient still ends up at 0%. If you spin out on flat terrain, adjusting Trainer Difficulty won’t do anything about that. It only affects simulation mode, so it has no effect in ERG mode workouts.

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I think that is one of the reasons. Others might be:

They don’t have the gears on their bike to climb the actual climb, at least not without grinding out of the saddle the whole way.

Some trainers (possibly older ones) can’t handle gradients that steep.

As a training platform some riders want to pedal downhill rather than just freewheel so low TD allows you to do this.

Gears work fine now and its way more fun now since i actually have to shift.
Makes climbs feel way more real and makes them more painful aswell :smiley:.

Thank you for your help.