The end of highly polluting petrol 2 wheelers? New tighter European emissions standards are being introduced for motorcycles and scooters. The new regulations will first be applied to newly-developed bikes from 1 January 2016, the official date at which the regulations will come into force, while existing models will generally have until precisely one year later – 1 January 2017 – before they have to comply. Euro 4 rules are nearly twice as strict as the Euro 3 regulations that have been in place since 2006. The rules vary depending on performance, but for most full-size bikes carbon monoxide emissions, currently limited to 2.0g/km (grams per kilometre), drop to a maximum of 1.14g/km, while hydrocarbon limits drop from 0.3g/km to 0.17g/km and NOx falls from 0.15g/km to 0.09g/km. What’s more, the Euro 4 also introduces a durability test, so manufacturers need to prove that their engines can still meet the limits after 20,000km of use.