Zwiftpower power curve issues

My last couple of rides/races seem to reflect wrong power data for 0s - approx 1min. I’ve seen some closed threads on the subject, yet it still is ongoing. Any updates?
ZP profile 256264

Update: This issue seems to be related to the processing of FIT files. The TTT ride I refer to below, is only based on live data (green bolt). Power calculations based on live data is known to be inaccurate as discussed in several other threads in this forum.

I’ve experienced a similar thing on my TTT last night. My average watt for the whole race was 257W. However, the 20min average was only 253W in the power curve. Tools like veloviewer and intervals.icu both calculates my 20min average to 265W, which is my best performance so far. This is not reflected in my profile or in the category average of my three best races.
ZP profile 1620579

No explanation but same experience. Posted in a new topic few hours ago (not familiar with the new forum)
« Why 1’ to almost 30’ left part of ZwiftPower power curves are flat, and high/middle W/kg values systematically underestimated? TDZ#4 @5pm today: 20m, 5m, 1m, 30s, and 15s are 3.4, 3.8, 4.8, 5.2, and 6.0 on zwift power versus 3.4, 3.8, 5.4, 7.7, and 9.8 on fit file from Zwift??? My profile is public. I’m probably not the only one.
Thanks »
Can anyone understand? Can anyone fix this?

The truncation of Zwift Power power curves below 1min doesn’t appear right to me. And it sounds like its got something to do with using live data.

I started using intervals.ICU to get a better idea of power curves. You can see a completely different picture in the short durations and a more organic hyperbolic shape to the curve.

Issue still ongoing. Event EVO CC Sprint race (id 1731112). My power data is wrong (no 20 min power, although race was 20+min, NC power lower than avg, incorrect 15sec power). @Zwift, any reply/update/explanantion?

Same issue here since months. My power data is wrong for all live data events like TTT.

It´s always around 5.1 - 5.2wkg for 1 min, 30sec and 15 sec.

For todays TTT ZP shows up 5.2wkg for 15seconds. Strava shows up 10.2wkg for 15 sec.

Have the same problem. 1 minute - 15s shows the same w/kg. The power curve is flat under for everything under 1 minute. The same powerdata is forwarded from Zwift to Garmin Connect and are shown correctly in Connect. Frustrating!!

Power curves still flat. What is going on on ZP ? Can you please fix this issue !

Didn’t happen to me but someone I raced against. Completely flat curve for 0-15s like it is stuck at 907W.

2nd place C Cat in this one if that helps solve the issue all: Zwift Power - Login

I am assuming the original data from the racer is good and that the processing of that data somehow is messed up.

Same issue in all events, both rides, races and TTs, in more than a month.
zp id: 1570438

I have the same problem for my last rides, flat power curve for approx 1min - 5 s. Is it something i have done or is it a bug in zwift power ?

I am seeing the same behavior 1, 2, 5, 10, 15, seconds Power Curve is a flat line on Zwiftpower. The data is also uploaded to Strava and Power Curve looks correct at that site. I checked the fit file for one of the events 2021-08-13-05-20-57 and the data and results shown on the standard view looks reasonable.

8/13/21 [DIRT Friday Morning Sprintapalooza]) 2.8w/kg 182w 198w 2.8w/kg 3.1w/kg 4.6w/kg 6.2w/kg 7.8w/kg 66.0kg 162bpm 183bpm 34km

ZP profile 3818585

This looks like its happening to lots of people. Any updates on what is going on?

It’s caused by you not saving your activities publicly. Restricted activities do not produce a .fit file indicated by the blue power bolt on your profile. The absence of a fit file produces a flat power curve up to 15s; in fact other CP values will be affected. Change your privacy settings and this issue will disappear.

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