The limit values currently applicable in the Federal Republic of Germany for exhaust gas emissions of motorcycles are much higher than those of passenger cars. They are no incentive for reducing emissions. A research project carried out at the Institut für Fahrzeugtechnik of the Technical University Berlin aimed at determining regulated and non-regulated exhaust gas components of motorcycles in various driving cycles. Using five selected vehicles, it was possible to demonstrate that by the use of catalytic converters and other measures, even stringent future limit values such as the ones provided for in Annex XXIII to StVZO (Road Traffic Licensing Regulations) for low-emission cars, or the new limit values for cars as of 1992, can be complied with. To do so, use of a closed-loop three-way catalyst is not always necessary. By using the pollution control technology described, a sufficient reduction of the emissions of the non-regulated components benzene and polycyclic aromatic hydrocarbons is achieved. The question of the catalysts' durability cannot yet be answered conclusively.
Abstract