Because of the steadily increasing improvement of the emissions situation with passenger cars, there is an increased desire for the emissions abatement of other sources, such as motorised two-wheelers. The emission standards recently proposed by the European Commission for 2003 will be followed by a further tightening of these limits from 2006. The paper gives an overview of the state of the art and of the potential of available emissions abatement techniques for different types of engines, divided per category and class of motor cycle. In an evaluation the expected time-frame for the feasibility of a practical introduction of different emission abatement techniques and their cost efficiency are discussed. An adequate emissions certification procedure and more especially an adequate test cycle is an extremely important instrument to assure that emissions in the field decrease in the same order as the tightening of the emission standards. The basic requirements of an adequate type test procedure, avoiding the shortcomings of today's test, are discussed and an approach for developing a new emissions test cycle is presented.
Abstract