Originally there was some loud noise when I went on shaking road. I have read about it in reviews too.
I have searched the source of noise by shakeing the scooter in my hand, it sounded like the battery pack. I have disassembled.
First pull up the plate sticker, remove the reflective fixer screw, remove both reflective, remove the two front lid fixer screw, pull to front to remove front lid. Pull out the battery pack.
There is around 1mm gap between battery and the aluminium hollow section. I have put rubber plate into the gap, and pushed back the battery, put back the lid, and reflectives. See miracle, the noise disappeared.
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