Nowadays, more and more people like to wear watches, especially mechanical watches. It is not only the crystallization of people’s precision manufacturing, but also a cultural heritage. Many friends in the use of mechanical mens watches will find that the watch will move more and more slowly. So what should we do if the mechanical watch goes slowly? What’s the reason for the speed of the mechanical watch? Mechanical watch can be divided into the following two types: manual chain and automatic watch. The mechanical watch on the chain by hand is powered by turning the winder by hand. The thickness of the movement is thinner than that of the watch on the winder, so the weight of the watch is relatively light. The watch with automatic chain is driven by the power generated by the left and right swing of the automatic rotating disk of the movement, but the thickness of the watch with manual chain is relatively smaller than that of the gold watch with automatic chain. The main reasons for the slow running of the mechanical watch are: insufficient activity and kinetic energy; the watch is magnetized; the oil mud in the movement is dry and so on. Generally, a watch can’t adjust the date and time from 9:00 p.m. to 3:00 a.m., which is easy to cause problems in the calendar drive wheel system inside the watch. Therefore, it is forbidden to adjust the date of the watch during this period. If the power and energy of the watch are insufficient, the watch will slow down or not walk. The automatic mechanical watch needs to be worn normally for about 8 hours every day. It needs normal and appropriate kinetic energy to support the travel time. It can support 36 hours of travel time if it is worn for 8 hours every day.