Anyway hows the issue with the motor/sensor?
I must say it does look like a sensor problem to me from the vid you posted.
When you get a sensor problem the esc cant work out the position of the rotor in relation to the sensors so it has to try and work out which channel to put power down to turn the motor forward, if that makes sence.
Hence the reason for it moving back and forth before it works it out and wants to go.
Try in the following order (of cheapness ). Sensor lead (make sure it is pushed into the sockets properly), Motor, then the only other thing it can be is esc.
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