A new four-stroke motorcycle, HONDA CG125, was chosen as test one without catalytic converters. Table 2 presents the main properties of the engine of this motorcycle. In this experiment, the chassis dynamometer (AVL 20 in.Motorcycle) used is located in Tianjin Motorcycle Technical Center, China. The testing was performed on this chassis dynamometer according to European driving cycle (ECE) 15 cycles. Two types of samples were analyzed in this study.