It does depend on performance, but for the majority of full-size bikes, the maximum limit for carbon monoxide emissions is moving to 1.14g/km from 2.0g/km. The NOx (nitrous oxide) limit is going down to 0.09g/km from 0.15g/km, and hydrocarbon limits are going down to 0.17g/km from 0.3g/km.
The government is also introducing a durability test, so bike manufacturers will have to show that their engines can still meet these strict new limits with 20,000km on the clock.
Noise emissions are also part of the legislation, which have required myriad changes by manufacturers, including redesigned exhaust systems – check out the Ducati 959 Panigale – and changes to the gearbox, for example.
Yes, a few things.
Fuel vapour contains more unburned hydrocarbons than exhaust gas. When you fill your tank, some of these hydrocarbons go into the atmosphere via a breather pipe. Euro 4 limits how much of this is allowed to escape, so manufacturers have to find a way to manage this.
New bikes will also have to have onboard diagnostics systems fitted. These measure and record the status of emissions management systems, and give status updates to mechanics.
All new-model bikes over 125cc will need to have ABS from January 1 2016, and any smaller bikes must either have ABS or a linked brake system. Any model that has been carried over has until January 1 2017 to comply with the regulations.
All new models also need to be fitted with automatic headlamp on (AHO) – or daytime running lights, with no switch to turn them off – and US-style side reflectors, which Europe had broadly managed to avoid, until now.
Finding innovative solutions to an issue like Euro 4 is part and parcel of the job for motorcycle engineers, so consumers are unlikely to experience much of an effect. We do expect there to be a surge in new motorcyle models, featuring the tech required to comply with the new regulations and that, in turn, may cause prices to rise.
However, for consumers not looking to the top end, there could be bargains to be had on bikes that can’t meet Euro 4 regulations and face being discontinued. The retro-inspired Kawasaki W800 is one such example we’d have our eyes on.