The unicycle uses the lever principle to close the resistance point of the load to the fulcrum (i.e., the wheel) to make its operation efficient, and also shares the load on the unicycle and the operator. Because unicycle makes it easy to move heavy or large loads, it is indispensable in construction sites, agricultural land and gardens.

Although the two wheeled handcart is relatively stable on the flat ground, the unicycle has high operability in places prone to imbalance, such as small, planked or raised roads, and is easier to control when unloading.

Because of the law of the center of gravity, it is very easy to overturn. It is strange that ancient Chinese people used it to carry people and carry people. It is a long journey and smooth and light. Therefore, its creator and the first driver must be a mechanical engineer with courage and knowledge. As for the shaft of a unicycle, its length, flatness and inclination, the height, straightness and inclination of the strut, and the square and elliptical shape of the wheel cover almost vary from place to place and from person to person.