The Use of Catalytic Aftertreatment to Meet Advanced Emissions Standards for Indian 2-Wheel Vehicles

Catalyst application efforts for 2-wheel vehicles equipped with small power plants are typically directed toward the identification and implementation of a catalytic solution that meets target mass emission requirements and has a minimal impact on the existing vehicle design and affordability. As a result of this, maximum conversions of the exhaust stream hydrocarbons and carbon monoxide are neither targeted nor achieved and the full benefit of catalytic aftertreatment is not realized. This paper presents the results of a study that examines the achievable tailpipe emissions of two Indian 2-wheelers through simple catalytic approaches. The two test vehicles are both motorcycles; the first is equipped with a 110 cm³ 4-stroke power plant and the second uses a 100 cm³ 2-stroke engine. Analysis of mass and modal emissions from both vehicles is used to compare and understand the efficiency and limitations of various catalytic configurations including catalyzed inserts and conventional matrix based catalysts. As reported the tailpipe emissions of both motorcycles can be reduced to less than 1.0 g/km HC+NO_x and 1.0 g/km CO, with a well designed catalytic system.