Middle motor and electric bicycle

The utility model provides a centrally-mounted motor and an electric bicycle. The centrally-mounted motor comprises a driving unit, a speed reducer unit, a clutch structure and a mounting shell, the driving unit comprises a stator assembly and a rotor assembly; the rotor assembly is rotatably mounted on the stator assembly; the speed reducer unit comprises a gear, a worm and a worm gear; the rotor assembly is meshed with the gear, one end of the worm is fixedly connected with the gear, and the other end of the worm is meshed with the worm gear; the worm gear is connected with the clutch structure, and the driving unit, the speed reducer unit and the clutch structure are installed in the installation shell. The worm, the worm gear, the gear and the like of the speed reducer unit are compact in structural design, large in transmission ratio and capable of achieving high-torque output, the design mode is small in impact load, stable in transmission, low in noise and good in noise reduction performance, meanwhile