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Power measurement trainer vs Vector

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Power measurement trainer vs Vector

Old 11-02-20, 10:52 AM
  #26  
drewtk
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As others have pointed out, your bike computer and trainer may be sampling the power readings at different intervals. Instead, try comparing the power readings of your pedals and trainer using Zwift at the same time.

Here's how: At the setup screen where you pick devices to connect, select the connect screen for the power device and leave that screen up. It should detect all available power devices, including your pedals and trainer, along with a LIVE reading from those devices. Leave that screen up and start pedaling (don't connect a power device). You'll see live power outputs from your pedals and trainer at the same time, read by the same computer.
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Old 11-02-20, 05:17 PM
  #27  
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Originally Posted by jadocs
Was the 25% to the positive or negative in terms of power? In other words were your Uno's telling you, you were putting out more power than you actually were or was it the other way around?
The OP had the 25% difference, I've been able to get everything close.
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Old 11-03-20, 11:20 AM
  #28  
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I find when I first start it up, the kickr tends to under or over report power... but as it warms up, it will converge w/ my quarq.

If they don't converge, either or both could be off somewhat. calibrate them repeatedly until they do converge.

-----------------------------

warm up both vector and kickr for 10 minutes.

calibrate your vector. spin down calibrate your kickr.
REPEAT this immediately.

Now set garmin to 3s power (display the 3s average) and zwift to the same.

Free ride and compare. they should now be close enough.

in workout/erg mode, zwift reports target, not actual. actual will fluctuate as you speed up and slow down. try holding a steady cadence and power and then erg mode will match your pedals close enough.

Last edited by nycphotography; 11-03-20 at 11:24 AM.
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Old 11-04-20, 10:41 AM
  #29  
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Originally Posted by nycphotography
I find when I first start it up, the kickr tends to under or over report power... but as it warms up, it will converge w/ my quarq.

If they don't converge, either or both could be off somewhat. calibrate them repeatedly until they do converge.

-----------------------------

warm up both vector and kickr for 10 minutes.

calibrate your vector. spin down calibrate your kickr.
REPEAT this immediately.

Now set garmin to 3s power (display the 3s average) and zwift to the same.

Free ride and compare. they should now be close enough.

in workout/erg mode, zwift reports target, not actual. actual will fluctuate as you speed up and slow down. try holding a steady cadence and power and then erg mode will match your pedals close enough.

You can prevent this by turning off erg mode power smoothing in the Wahoo app for the Kickr
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Old 11-04-20, 12:30 PM
  #30  
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Originally Posted by mvnsnd
You can prevent this by turning off erg mode power smoothing in the Wahoo app for the Kickr
I don't bother with the wahoo app except for spin down calibration, but this setting is still good to know. Thanks
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Old 11-05-20, 02:37 AM
  #31  
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That's a big discrepancy, turn off ERG and make sure you set both to average 3s or so.

Our Tacx Neo reads within 10-5W to my left only Stages and tracks very accurately with my Quarq.
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