Electric motor weight depends on the age and size of the motor. A typical motor for a blender or small kitchen appliance may weigh less than a pound, while large industrial motors can weigh many tons.
The 5 HP Leeson reversible electric motor weighs 84 pounds. The 3 HP version of the same motor weighs only 46 pounds. The weight of a motor can also depend on what type of materials are used to construct it. Aluminum and titanium weigh far less than cast iron or steel. Better materials make it possible to manufacture lighter weight motors, but in some cases heavier motors are better for stability.