Homemade Moped

Emissions
Mopeds can achieve fuel economy of over 100 mpg-US (2.4 L/100 km; 120 mpg-imp). The emissions of mopeds have been the subject of multiple studies. Studies have found that two-stroke 50 cc mopeds, with and without catalytic converters, emit ten to thirty times the hydrocarbons and particulate emissions of the outdated Euro 3 automobile standards. In the same study, four-stroke mopeds, with and without catalytic converters, emitted three to eight times the hydrocarbons and particulate emissions of the Euro 3 automobile standards. Approximate parity with automobiles was achieved with NOx emissions in these studies. Emissions performance was tested on a g/km basis and was unaffected by fuel economy. Currently in the United States, the EPA allows motorcycles, scooters, and mopeds with engine displacements less than 280cc to emit ten times the NOx and six times the CO than the median Tier II bin 5 automobile regulations. An additional air quality challenge can also arise from the use of moped and scooter transportation over automobiles, as a higher density of motorized vehicles can be supported by existing transportation infrastructure.