Polar Speed Sensor going too slow

Hello, I’d like to know if there is any way to calibrate a polar speed sensor. I’m using a roller trainer.
The cadence sensor is working well, but my speed goes suddenly low down to less than 8 km/hr.
I already chose the wheel size but it doesn’t seem to work well.
Please help

Hi @Claudio_Soto

Welcome to the forum.

Zwift takes the wheel speed broadcast by your speed sensor and the power curve of the trainer you select on the Pairing Screen and converts that to virtual watts. With those watts, the weight entered, height entered, in-game bike used, in-game drafting (Tri and TT bikes get no drafting boost), in-game wheel set, in-game road surface, and in-game virtual elevation changes your in-game speed is determined.


That look familiar, :thinking:

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Thank you for your quick answer!

So do you think the sensor is not having problem and it’s just about the different parameters used?
(I’m probably too heavy right now)

I selected unlisted rollers

Thank you again

Your speed will go down if you are going uphill in game.

when you go up hill you need to change gears to your big front gear and small back to go faster.


Thanks a lot