I just noticed this today:
While a feather power-up is active, the watts/kg shown is overstated.
Mine went from 2.30 to 2.56 and then back to 2.30. This aligns perfectly with the game temporarily reducing my weight by 10% while the power-up is in effect.
I’m not sure I understand what you’re saying. The feather PU does temporarily reduce your weight (in-game), so shouldn’t the w/kg increase correspondingly?
the feather has always done this as seen in the Zwifters Nearby list every time you use it
I always thought that was how it was supposed to work. Seeing that also helps me understand how much I need to ramp up when the feather expires if I want to maintain pace.
I’m talking about the Ride Stats panel on the left hand side of the HUD. It’s saying that my average wkg for the whole 40 minute ride so far goes from 2.30 to 2.56 and back to 2 30.
That’s just wrong. The temporary weight reduction shouldn’t be applied to that full-ride stat.
I agree that data is mostly used to understand real numbers so it makes sense to have it ignore things like feather and anvil PUs.
I saw and reported the same issue a while back. Definitely a bug.
Ah, got it. So it’s like it changes the denominator in the calculation during the time the PU is active, and then changes it back when it expires. That definitely sounds wrong.
I wonder if the anvil has a similar issue.
As the feather causes your weight to be reduced, this is what I would expect to happen.
Hey, I can happily ignore the transient absurdity 
The “average w/kg” field in the Ride Stats panel is for your entire ride. If you ride for an hour at 3.0 and then use a feather your average w/kg will show 3.3 for the entire hour you’ve been riding.
This should happen in the riders nearby list, as this is instantaneous wkg, but really shouldn’t happen in the ride stats calculations.
What happens if you end and save your ride in the middle of a feather powerup. What gets saved?
The feather power up should not drastically alter what is shown in the ride stats for average watts/kg.
Here is a recent ride.
Yes it is. Of course that’s not how it should be behaving. I’ve never noticed that sort of impact before and am curious if others have.
Does it stay the same after the power up period ends?
It changed for the duration of the power up and then reverted to “normal”.
No. It reverts. As per my original and subsequent posts. Transient absurdity.
TY. I’ll flag with our developers.
