Insufficient battery power: charge the battery
Poor contact of battery contact: adjust contact position or polish contact;
Motor internal carbon brush, wire, winding virtual welding, virtual connection: repair or replacement of best mid drive electric bike motor.
Bad contact between the safety tube and the seat in the battery box: adjust or replace it well;
Speed regulation hand handle inside photosensitive film inside the tube there is dirt: clean or replace photosensitive film, wipe the sensitive tube, still cannot troubleshoot: replace speed control hand handle.
There is a fault in the controller: replace or repair the controller;
Speed control hand seems to break the lead wire: replacement or repair lead;
Malfunction of brake power off switch: adjust or replace brake power off switch;
Poor contact after power lock ablation: replace or repair power lock;
Virtual connection in the line: reinsert it to make it in good contact.