Allow 1 Watt Increments in Erg Mode

(Keith Malarick) #1

TrainerRoad allows 1 watt increments in erg mode but Zwift only allows 5 watt increments. Why is this?

(Jordan Rapp) #2

Hi Keith,

We actually allow single watt increments. The 5w increment is strictly visual. It’s a holdover from when we had a larger percentage of users on classic trainers and before ERG mode was as universal and reliable as it is currently with the standardization of communication protocol. Whatever you see in the workout preview is the exact wattage that gets sent to your trainer in ERG; we just use the rounding in-game for display purposes. 

Always looking to improve Zwift, though, so thank you for the feedback.

Ride On,


Zwift Game Design

(Keith Malarick) #3

Interesting, didn’t realize that… Any chance you would consider displaying the actual wattage that is being sent to trainer? I realize a watt or two doesn’t really matter but just seems funny to be sending one number to the trainer but displaying another. For example when bumping up a couple percent would be nice to know exactly what wattage I am bumping up to.


(Jordan Rapp) #4

Hi Keith,

It’s definitely something we’ve discussed. Feedback from users like you definitely matters. So thanks!

(Chris Holton) #5

I hadn’t realised this either, so when you increase FTP by 1% but the displayed watts doesn’t change, does the actual power increase but just not by enough to affect the rounding?

(Jordan Rapp) #6


Yes, the actual power will always change by 1% up or down - rounded to the nearest 1w. But the display only changes in 5w (rounded) increments. I realize this can be a bit confusing. So, yes, changing FTP bias by 1% always makes it easier or harder, even if that’s not reflected in the display because the net change was not enough to trigger a change in 5w rounding. For example, if you are riding at 302w, that will show as 300w. If you drop it down by 1%, that would drop the power to 299, which would still show as 300w, but the precise values - 302w & 299w respectively - are what would be sent to the trainer.