poor power measurement Drivo II / Quarq Red Dzero

[tomvi]

Hi, do you have any experience with the Elite Drivo II trainer and also with the bike that is equipped with a power meter? Elite everywhere says their accuracy of power measurement is +/- 0.5% but I still have a difference between Powerball measuring on a bike (Quarq) and measuring in a trainer about 20W. Of course, calibrations are done, tested on the app from Elite and Rouvy several times, lengths of a training min. 1 hour.
Thank you for any comments. Tomas

[Elite Admin S]

Hi

It's good to remember that the measure of some power sensor may be different from the one done by the trainer because of the lost of power on the transmission (expecially on the chain). This is true expecially for pedal power sensor on anterior crown power sensors (as our trainers measure power on the hub)In some cases the power lost may be up to a 5%.

I'll link some external sources:

https://www.dcrainmaker.com/2018/12/how ... ssues.html
https://www.bikeradar.com/news/friction ... fficiency/
https://www.ceramicspeed.com/en/cycling ... -friction/
https://www.cyclingpowerlab.com/Drivetr ... iency.aspx

[tomvi]

Hi Admin, thank you for your reply. I know, that measurement can be different, but i have 20W on the 200W average power. I have new bike, on the sram red etap, with clean and lubricated chain. If power lost will be 5%, ona 200W average, you can lost 10W, BUT not 20W.
I've read many tests where the difference between a wattmeter on a wheel and watts from DRIVO 2 was 3 to 5 watts. Also in this forum are users who have the same results both on bike and on Drivo 2.

I bought DRIVO 2 because it is reported to have a measurement accuracy of + - 0.5%, but I measure with 10% error which is unacceptable.

Tomas

[iosman]

Hi Admin, thank you for your reply. I know, that measurement can be different, but i have 20W on the 200W average power. I have new bike, on the sram red etap, with clean and lubricated chain. If power lost will be 5%, ona 200W average, you can lost 10W, BUT not 20W.
I've read many tests where the difference between ometv a wattmeter on a wheel and watts from DRIVO 2 was 3 to 5 watts. Also in this forum are users who have the chatroulette same results both on bike and on Drivo 2.

I bought DRIVO 2 because it is reported to have a measurement accuracy of + - 0.5%, but I measure with 10% error which is unacceptable.

Tomas

thanks for the information.

[flimps]

A year has gone by and looks they have not fixed it.
My drivo reads 10-15 watts above any other powermeter.

They said the difference lies on that the powermeters reading on the pedals or cranks, chain dispersion, etc. The reality is wahoo provides same reading as pedal and cranks powermeters while drivo does not.

The problem lies in their BLE connection. Either they dont want to say they know this or acknowledge.

Returning my drivo this saturday. End of story