How does the UCI scan for hidden motors in race bikes? This video posted to Instagram by Claudio Cucinotta reveals the process of scanning a bike, in which a small tablet is used to check the frame for a hidden motor.

Controlli @uci_cycling per verifica presenza #motorini in telai e ruote @bardiani_csf #greenteam #rideclean

A video posted by Claudio Cucinotta (@claudio.cucinotta82) on Feb 12, 2016 at 7:12am PST

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We believe the UCI is using the magnetometer sensor built into a tablet to scan for the magnetic fields produced by the magnets in a motor. It could be using a dedicated app to do this, but it could just as simply be using the compass. 

The bike being scanned belongs to a rider on the Italian Bardiani – CSF Pro Team.