The purpose of this paper is to study how the transmission ratio affects the working process of electric motorcycles. To achieve this goal, an electric motorcycle simulation model, including a dynamic model and a battery model, was established based on mathematical models and using MATLAB SIMULINK software. A simulation model is used to determine speed, electric motor torque, and power consumption characteristics with changing gear ratio. Through simulation study, the article shows that when increasing the gear ratio from 3 to 4.587, the speed and the moving distance decrease from 46 km/h to 44.6 km/h, respectively, and from 784 m to 743 m, while electricity consumption increases by 0.16%. Through simulation, a researcher can optimize the power consumption and dynamics of an electric motorcycle by varying the gear ratio.