Problem with Saris speed sensor

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jules.b
Posts: 16
Joined: Thu Feb 25, 2021 3:06 pm

Problem with Saris speed sensor

Post by jules.b »

I've just started using my trusty PowerPod on my TT bike, planning to do some cdA analysis. It is paired to a Rotor DFPM and a Saris speed sensor fitted to the front hub. Weirdly the reported wheel speed is well below actual, and the recorded distance is also nearly half the actual. The examples below relate to a 34 km ride averaging 35 km/h. ISAAC shows it as 18.5km at around 19km/h.

I've re-run the setup, pairing and calibration process and the outcome is the same. Wheel size is set correctly I think. The PowerPod is working well on my other bike. The speed sensor is new and has a fresh battery. Has anyone experienced this issue before and is there an easy fix?

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jules.b
Posts: 16
Joined: Thu Feb 25, 2021 3:06 pm

Re: Problem with Saris speed sensor

Post by jules.b »

iBike file attached if relevant, thanks!
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Velocomp_02_25_2021_1641_33_km.ibr
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Velocomp
Velocomp CEO
Posts: 7793
Joined: Fri Jan 11, 2008 8:43 am

Re: Problem with Saris speed sensor

Post by Velocomp »

I'm not familiar with a Saris speed sensor. Please send photos of it as mounted on your bike. Are you using it with a magnet? If so send photos of magnet/sensor too.

Also, there is a huge amount of noise in the speed sensor channel; this is the likely cause of low speed readings. You might want to try removing the sensor battery, putting it in backwards for a moment (to reset it) then reinstalling it.
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John Hamann
jules.b
Posts: 16
Joined: Thu Feb 25, 2021 3:06 pm

Re: Problem with Saris speed sensor

Post by jules.b »

Apologies for the slow reply. I followed your advice and soon concluded that the sensor is defective. I swapped it for another which works just fine. PS I just bought an Aeropod
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