Along with social progress, people pay attention to health. Modern people choose the gym to maintain posture and body functions well, therefore, the gym popularize everywhere. Popularity of expensive fitness equipment to bring a lot of convenience, but different users share of fitness equipment have different condition, often caused damage by use, which is the most important factor for the material fatigue damage. This study chose the exercise bike parts “self run bushing” to create a fatigue life assessment mechanism. In this study, to the fatigue analysis was conducted, by using finite element analysis according to the material S-N curve and Miner cumulative damage theory in a series of cyclic loading. To analyze fatigue life, analytical and experimental studies through mutual verification were conducted which can obtain the expectation life period of the self run bushing. The load spectrum based on different user can also be considered in this study. Based on the design frequency from different users, after the study of distribution of reliability and failure, the most appropriate time-out and the best replacement time can be obtained.