Gear shifting system of miniature transmission at five-way position of bicycle

The invention discloses a gear shifting system of a miniature transmission at a five-way position of a bicycle, and relates to the miniature transmission at the five-way position of the bicycle. According to the gear shifting system, four steps are arranged on the top of a transmission upper cover from bottom to top and sequentially comprise a first step, a second step, a third step and a fourth step, tension spring guide grooves are formed in the left side, the right side and the rear side of the second step, a gear shifting fork hole is formed in the first step, and a gear shifting driving lever and a contact of a gear shifting fork are installed in the first step; the second step is provided with a gear shifting sliding block frame; a front pressing plate and a rear pressing plate are arranged on the third step; a cover plate is arranged on the fourth step; the two ends of the tension spring are connected to tension spring hanging lugs, and the middle point of the tension spring is fixed through a screw. A