The engine is the distinctive element of a motorcycle and determines its character and image: two-cylinder, single-cylinder, in-line 4 cylinders, V, L. In the case of electric motorcycles, the engine is replaced by the electric motor. Its function is to convert the electrical energy supplied by the battery into mechanical energy to move the bike.
The components used to rotate the shaft of the electric motor are the stator and the rotor; the first is fixed while the second is integral with the shaft and rotates with it. The rotor is rotated by the magnetic field generated by the alternating current flow passing through the stator windings. The motion of the rotor is transmitted to the pinion by different types of final transmission: through a gear, a belt, a gearbox. There are also cases in which the pinion is fixed directly on one end of the motor shaft.

In MotoE, the motor is permanent magnet type (Permanent Magnet AC Motor - PMAC) and it transmits motion to the wheel through a fixed ratio reduction gear and a chain.
An electric motor has a power curve that rises with the rotational speed for most of the range of use until it stabilizes at high revolutions. The torque curve, on the other hand, has its maximum already at zero rpm and remains constant for a large part of the range of use until it halves at the maximum number of revolutions.
The torque curves of the electric motor and the endothermic engine have opposite trends with major effects on the behaviour of the bike. Referring to the judgments of the riders of the MotoE, exiting from a low speed curve, therefore at low rpm, the torque of the bike is surprising even at small rotation of the throttle. In fast corners, on the other hand, the electric motor works in the area where the torque value has dropped and you can fully twist the throttle; something unbelievable, for example, with a Moto2 that in the same scenario has the maximum engine torque.

One more important effect of the motor on the riding style of an electric motorcycle is the handling. An endothermic engine is characterized by considerable moving masses, whose gyroscopic effect acts to reduce the handling of the bike. This can be reduced by varying the engine configuration but cannot be fully eliminated. In an electric motor, the only rotating mass is that of the rotor and is extremely little. As a consequence, its gyroscopic effect of very little too. For this reason, an electric motorcycle is much easier to handle than a motorcycle with an endothermic engine of similar weight.

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