Hello All!
I wanted to jump in to add some clarification around how a trainer’s resistance floor- the minimum resistance the trainer can apply- may affect your experience with virtual shifting. The topic is more common when discussing ERG mode, but is applicable here as well.
Depending on a variety of variables, gear changes at the lower range of virtual (and even mechanical) shifting may not result in a noticeable change in resistance if you’re targeting an output below the trainer’s minimum resitance. The variables include:
- Rider output- If your output is above a certain threshold in power or cadence, in addition to any of the other variables, the lowest gears may not produce any noticeable change in resistance
- Resistance floor- Smart trainers can only remove resistance to a certain limit, at which point shifting down will not result in any change. Most Wahoo trainers have a resistance floor of about 50 watts. The Direct XR has more robust internal gearing and has a resistance floor of about 100 watts.
- Road Gradient- Flat and downhill roads in Zwift will add very little or no resistance against your pedaling, similar to real life. Lower gears may fall below the resistance floor if the gradient is 0 or negative, but be perfectly useful on a steep climb.
- Trainer difficulty setting- This setting modulates how steep road gradient feels on ascents. At 0%, all roads are flat. At 50%, an 8% climb in Zwift triggers 4% gradient simulation on your trainer. At 100%, some of the steeper roads and gears may be at or beyond the maximum resistance level of your trainer.
- Gearing range setting- While all virtual gear ranges in Zwift have the same gears, the gear ratio of each gear can be quite different between each. Flat road gearing will have higher gear ratios to help keep a high top speed, while climbing gearing has very low gear ratios at the lowest gear to assist climbing up steep gradients.
If you’re not experiencing resistance changes on only one end of your gear range, you may want to adjust your gear range or trainer difficulty setting to better suit the riding you’re doing at the moment. If you are not experiencing any resistance change at all across any virtual gears, I definitely recommend taking a look at this separate thread or reaching out to Support.