The structure of a classic self-energizing synchronizer is presented, and a simulation model is developed for analyzing the synchronizer performance. The self-energizing synchronizer has a disk spring and several energizing teeth on the sleeve for increasing the shift force. Besides, the asymmetric arrangement of chamfer teeth is applied to increase the torque for rotating ring and shift gears smoothly. The parameterized model of the typical synchronizer is developed with ADAMS for studying the synchronizer performance. In order to truly reflect the reality, the teeth of the claw plate are connected to the gear ring through bushing force alone, and the stiffness coefficient are obtained through the analysis of finite element model. Based on the dynamic model, the behavior of synchronizer with asymmetric arrangement of chamfer teeth, and the energizing effect of stiffness of the disk spring are studied. The simulation results can be used to design the synchronizer.