Question: what is the difference between bs iii and bs iv?
Answer: The classification of vehicles according to classes is common for both the BS-III and BS-IV emission standards. For motorcycles, the change slashes the emissions by 25 per cent for CO and 40-50 per cent for HC+NOx. BS-IV is fighting a war on carbon monoxide (CO), hydrocarbons (HC) and other nitrous oxides (NOx).