Fuel economy and volatile organic compound exhaust emission for motorcycles with various running mileages

The implementation of control measures for motorcycles in urban areas depends on the establishment of baseline measures for fuel economy and emission characteristics. In this study, the fuel economy of motorcycles was determined to be 34.7 ± 1.4, 32.6 ± 1.8 and 29.5 ± 2.5 km L ^–1 for regulation phase V, IV, and III motorcycles, respectively. For regulation phase V motorcycles, the average emission factor was 84.3 ± 40.9 g L ^–1 for CO, 29.4 ± 13.1 g L ^–1 for HC, 8.0 ± 2.3 g L ^–1 for NO _x , and 2098 ± 109 g L ^–1 for CO ₂ . A comparison of the fuel economy of regulation phase III and IV motorcycles with that of regulation phase V motorcycle showed reductions of 15% and 6.2%, corresponding to increases of 156% and 48% in CO emission, increases of 84% and 9% in HC emission, and decreases of 30% and 17% in NO _x emission, respectively. Based on fuel economy, the emission factors of a total of 67 volatile organic compounds(VOCs) were 25.2 ± 8.0 g L ^–1 for a running mileage of 5,231 ± 4,353 km, with emissions increasing to 47.1 ± 19.8 g L ^–1 for a running mileage of 47,617 ± 8,568 km. The exhaust of VOC groups profiled included paraffins (38–45%), olefins (9.7–15%), aromatics (38–48%), and carbonyls (1.8–3.0%) for various running mileages. Toluene, isopentane, m,p-xylene, o-xylene, 1-butene, 1,2,4-trimethylbenzene, ethylbenzene, n-pentane, and benzene were the main VOCs in motorcycle exhaust. Regarding the ozone formation potential of VOCs, 1-butene, xylene, isoprene, toluene, 1,2,4-trimethylbenzene, propene, and 1-hexene were the most abundant species in motorcycle exhaust.