On July 4, 2014, India finalized the fourth stage of emission standards for motorized two-wheeled vehicles. The Bharat Stage (BS) IV standards will go into effect for type approval of new motorcycle models in April 2016, and for all motorcycle models in April 2017. The new standards tighten the HC+NOX emission limits compared with the existing BS III standards by 23%–60%, depending on motorcycle category. The other significant change to the regulation is the adoption of the Worldwide Harmonized Motorcycle Test Cycle (WMTC) as the mandatory test cycle. With this change, India has harmonized the testing cycle as well as the definition of motorcycle categories as per United Nations Economic Commission for Europe (UNECE) Global Technical Regulation 2 (GTR-2). In addition, the new regulation establishes the first evaporative emission standards for two-wheelers in India. Lastly, BS IV establishes that crankcase emissions form BS IV motorcycles are prohibited from release into the atmosphere.