In a transmission, one of the most important parts is the gear shift system. As its function is to control the correct change of gears and when it occurs, one can say that the gear shift system is one of the responsible for the transmission action, and, on a higher scale, for a important part of the vehicle operation.
When designing new gear shift systems, it is important to know the loads in which the system is submitted to in order to properly define the design parameters during the project, such as materials, geometry or assembly, however, it is common that these values are unknown for most, due secrecy of the companies or even due unavailability of detailed studies on the matter. There are several ways to obtain the loads, stresses and other general parameters that are acting on the components of such systems, but computational simulation can be seen as an important tool, due its overall low price, quick results and possibilities of working with different load conditions simultaneously.
Finite Elements Analysis, or FEA, would give precise data on the structural behavior of the system components to begin working on new design possibilities. This paper presents a study on a drum based gear shift system applied to a small engine motorcycle, in which a FEA analysis was performed in order to determine the internal loads. Different conditions were compared, and with the results of the analysis, it is possible to design new gear shift systems.