My bike started making a squealing sound. At first I thought it was dirt on the disc brakes, but saw that when I put on the brakes, the noise stopped until I let the brakes off. Also the noise stops when I quit using the pedal assist or throttle. Appears to be related to using the motor. Any ideas? just a high pitched squealing sound, not too loud
Not that uncommon. Start with adjusting your brakes or having your brakes adjusted:
https://radpowerbikes.zendesk.com/hc/en-us/articles/115004786874-Brake-Adjustment-Guide