The invention relates to a linkage mechanism for combining two wheels of a motor vehicle to basically solve the problem that due to the fact that an original motor vehicle is provided with only one wheel, the instability exists, and besides, the problem that due to the fact that the stability is pursued blindly, the flexibility is lacked can be solved through the simple and integrated improved structure. The linkage mechanism is simple, most part of the linkage mechanism can be covered inside a shell body through a first support and a second support, and a frame can bear most swinging force.