Quarq DZero power meter holds wattage indefinitely when user stops pedaling

Hey Zwifters,

A few users have reported that their Quarq DZero power meter holds the last sent wattage value indefinitely when dropped. This is over BLE.

I’ll update this post with new information as we receive it. Thank you!



Yep, I get this when pairing the DZero over BLE to the mobile companion app. When paired directly to a mac mini over BLE, I get constant drop-outs to zero (both power and cadence). Basically the DZero is completely unusable with Zwift over BLE. I have the same issue with 2 different DZero units. I raised an issue for this months ago but have not have any response yet.

A year on and still no fix for the DZero on Zwift?

Come on Zwift!!

Well it’s nearly 2020 and this still hasn’t been fixed. I’m getting snide comments from other users on descents and today I worked out it’s messing up my Training Peaks data! I thought that it was just a display issue but the power value really is latching and skewing my power results massively. I guess I can change to ANT+ but I’ve found BLE to be a much more reliable connection. Come on Zwift, lets have a happy new year. It’s not even difficult to detect. If cadence = 0 then power = 0. Zwift recognises I’m freewheeling downhill, most like based on cadence so one of these will probably do the trick:

if User_Cadence is == 0 && User_Power > 0
then User_Power = 0
end if


User_Power = 0
while (User_Cadence is == 0 && User_Power > 0)

Come on Zwift, give us a late Christmas Present!

Fix this!

Same problem here. The only way to stop the never ending power/cadence is to perform a counterclockwise spin. Please Zwift fix this issue.

I hope this will be fixed any time soon, as this has been going on for a long time.
Please Zwift, make it possible to find more than one device over BLE.
ANT+ is no option for me, as I experience a lot of signal drops over ANT+, ruining my races, which was the reason I was happy to be able to switch to BLE (from the beta onwards), for then the signal drops were gone. But I would love to uze my Quarq DFour pm again, next to my Taxc Neo

Bump. Just found this out today. It’s actually worse than the OP suggests. When you stop pedaling, it will, more often than not, hold the same wattage and cadence as before you stopped. Seems like a REAL easy way to cheat and produce garbage training data, ie lay down 500W, stop pedaling, then just watch it hold 500W indefinitely…

Is this a Quarq issue? I believe Stages and Power2Max lets you select in their firmware if you want to record during zero cadence, but the Quarq/SRAM software has no option to do this…

Is there any solution for the problem? I have the same BLE power behaviour on the SRAM AXS app. Maybe not a Zwift Problem?

I experienced this issue back in 2018 and immediately reported it to Zwift, but here we are two years later and it’s not fixed. The work around when you stop pedaling, is to back-pedal a bit, or even do a low spin at 10RPM.

Yep. Frustrating.
Thanks Daniel.

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The problem was my iPhone, not Zwift or SRAM power meter. It works fine when I connect my computer directly with bluetooth. I have also received an answer directly from SRAM.

SRAM Answer >>> Request #92566
In the ANT+ standard when the power value goes to zero the previous message is repeated. Since this is a standard within the ANT+ spec both power meters and head units know how to interpret the data. The head unit will go to zero once three repeats are received, This is why you get four repeats of power when you stop pedaling and then the power goes to zero.

Since we use this in ANT+ we mirrored it into BLE. BLE does not have a standard when it comes to power measurements, therefore some software/head units see three repeats of power and know that is zero watts and some software/head units will repeat the last value until cadence is measured again.

I hope this helps to clear things up! If you have any further questions please let me know.


Alex P


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