Abstract: Analyzes the working principle and structural characteristics of the random fatigue test rig for motorcycles, then a new fatigue-simulated time domain control technique is proposed and put into operation for the electro-hydraulic servo system of the tester. A multi-level hierarchical fuzzy controller is thus designed to control the test rig to track expected input signals and, finally, implement the real-time control of the electro-hydraulic servo system. Vibration testings have been done on the tester for various motorcycles of different sizes, and the results showed that the test rig can fully meet the testing demands of the motorcycle's reliability, thus providing a new way to the fatigue testing for either the whole motorcycle or its parts.