Motorcycle manufacturers usually update their products every few years. Sometimes they’re massive modifications which fundamentally change the looks, performance and handling of the bike, but sometimes they’re little more than under-the-skin updates, with apparently meaningless changes to the end user and a selling point of ‘Euro-whatever’ compliance to justify the inflated price tag.
It seems like a whole lot of bureaucratic nonsense to many riders and, over the past few years, bike manufacturers have refreshed their ranges with updates to meet the latest ‘Euro 5+’ standard – but what does that even mean?
To understand, we have to go back over a quarter of a century, when a new European-wide ‘Euro 1’ standard was brought in. What was originally meant to be a way of controlling exhaust emissions has arguably influenced motorcycle development far more than even MotoGP racing over the same period.
Put simply, failure to meet the latest emissions standards means a mass-produced motorcycle cannot meet type approval to go on general sale to the public. It means that millions are being invested in making our motorcycles cleaner and more efficient, and engineers are always looking for clever ways in which to meet the directives without massively impacting on performance.
As the ‘+’ suggests, the Euro 5+ standard is not a full step up from the strict Euro 5 regulations brought in at the start of 2020, rather a modification aimed at ensuring emissions levels remain low throughout the bike’s life cycle, and not just under laboratory conditions when it is new.
A brief history of Europe’s emission standards
Emissions standards are nothing new, having been a consideration for vehicle manufacturers since the 1970s, but the regulations often varied from country to country and, in the case of America, from state to state.
The 1990s saw leaded petrol phased out, and the first European-wide standard, Euro 1, was introduced for cars in 1992. Designed to reduce harmful emissions like nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC) and particulate matter (PM), it effectively meant all cars needed to be fitted with basic catalytic converters, while fuel injection systems – which effectively meter fuel going into the engine more accurately – made traditional carburettors obsolete.
It would take seven years for motorcycles to be regulated in the same way, with the first Euro 1 standard for bikes coming in during 1999, when catalytic converters started to appear on motorcycles for the first time. Euro 2, with tighter emissions limits, appeared less than five years later, while all new machines built after 1 January 2006 needed to meet Euro 3 regulations. By this time, pretty much every new motorcycle was running fuel injection to allow more accurate delivery of petrol, but in most ways they weren’t all that radically different to the machines we’d ridden pre-Euro 1.
Entering the electronic age
Although Euro 1, 2 and 3 came in rapid succession, Euro 3 remained the standard for over a decade. Euro 4, however, was to be a massive step forward and would require some out of the box thinking from design engineers. Applying to new type approvals from 1 January 2016 (with a year’s grace period for existing models) Euro 4 mandated more than just tighter tailpipe emissions.
Safety also became a factor, with ABS a legal requirement on motorbikes over 125cc and permanent daytime running lights also needed in order to meet type approval. Noise limits also became more of a factor, while standardised on-board diagnostics (OBD-I) didn’t mean much to the everyday rider but helped detect faults in advance, and therefore maintain emissions compliance.
This led to the widespread introduction of high-precision lambda control sensors and the fabled orange engine management warning light. The standardised system meant code readers could be plugged into the bike’s ECU and issues identified easily.
Introduced in 2020, Euro 5 tightened emissions dramatically yet again. By now, ride by wire throttles and sophisticated engine management systems were the norm. Stuff like charcoal canisters and bigger catalytic converters came in and engineers were finding new ways to meet the regulations while maintaining performance.
Closed loop fuelling, where the ECU monitors the O2 sensors in real time and adapts the fuel/air mixture accordingly, has become commonplace, as have more accurate electronic, or ride-by-wire, throttle systems.
Sometimes, though, these engineering solutions can be quite crude, often just increasing engine capacity to maintain the same levels of performance that would otherwise be lost through the addition of all the emissions gubbins. Conversely, many solutions are hugely innovative; shaving grams off engine components to reduce internal friction, developing faster processors and working on finer fuel atomisation to maximise efficiency.
A new onboard monitoring standard, OBD-II, also came with Euro 5, which means your bike is even more clever when it comes to understanding what’s happening inside its cylinder bores.
And this, in many ways, is at the heart of what Euro 5+ is about. While it doesn’t move the goalposts in terms of headline emission figures, it’s about making sure the vehicle maintains its efficiency throughout its lifespan, and not just in laboratory conditions when the bike is brand new. Without going granular into the details, a Euro 5+ motorcycle should be able to detect any emissions-related faults earlier and more accurately – and that diagnostic data should be easier to access too.
All the emissions equipment on our bikes needs to be more durable, especially the catalysts and O2 sensors, and as a result engineers have had to work on optimising combustion chamber design, reducing internal engine friction, fine tuning the fuel mappings and ensuring better management of the heat generated by the engine. The regulations should mean bikes are now able to deliver the same levels of reduced emissions in the real world as they do under test conditions.
What’s next?
One thing’s for sure, things won’t stop at Euro 5+. The car industry is already a few steps ahead of our two-wheeled world, with their Euro 7 standards set to come in later this year. Things like brake and tyre dust emissions are also coming under scrutiny and although no dates have yet been set for a Euro 6 standard for motorcycles, you can be sure this is one topic that is set to evolve over the years to come. While the drive towards complete electrification seems to have slowed, engineers will need to continue to make internal combustion engines cleaner burning if they are to avoid being legislated out of existence.
As an indication of how emissions laws have made motorbikes cleaner, Euro 1 dictated a maximum 13 grams of CO per kilometre ridden. This was more than halved, to 5.5g/km, with Euro 2, coming down to the 1g/km brought in under Euro 5. In the same period, NOx emissions have reduced from 0.3g/km to 0.06g/km, while HC has come down from 3g/km to 0.1g/km. It really has cleaned up our engines massively.
Of course, there are plenty critics of this increasingly strict regulation. R&D costs have increased, something which is generally being passed on to the consumer, while the added emissions equipment increases the weight of our bikes too. It’s also increasingly difficult to modify modern bikes, which has always been part of the joy of motorcycle ownership for some bikers. In many ways the job of the motorcycle designer has changed massively too, and the quest is no longer to make faster and lighter motorcycles, but to focus on usability, character and adjustability, as well as compliance.
Sportsbikes, in particular, have seen a decline in popularity over the past two decades, perhaps not only because of the commonly cited global financial crisis of 2008, but because the need to make bikes meet ever tightening emissions laws doesn’t fit well with the desire to make lighter and more powerful motorcycles, especially when racing laws won’t allow for bigger engine capacities.
Aprilia and Ducati, for example, have increased the size of their sportsbikes from 1000cc to 1100cc in order to meet emissions laws without sacrificing performance, but they are ineligible for racing. Meanwhile, Suzuki withdrew its flagship GSX-R1000R rather than reengineer it to meet Euro 5 although now, after a three-year absence, the GSX-R is being reintroduced with a Euro 5+ engine.
Despite having bigger throttle bodies and a higher compression ratio, and being fitted out with a new crankshaft, crankcases and pistons, the 2026 GSX-R1000 is down around 8bhp on its near decade old predecessor (195bhp to 203bhp) – demonstrating just how much of a challenge it is to maintain peak performance while reducing emissions.
And the legislation brings issues when it comes to sales too. The introduction of Euro5+ at the start of last year meant that manufacturers and dealers had to pre-register any bikes that couldn’t meet the new standard, in order to be able to sell them on as second-hand bikes.
While that meant there were some good bargains to be had, it also meant dealers found their showrooms stacked to the rafters with loss making stock in the middle of winter. While few can argue that today’s bikes are cleaner, more refined and more reliable than they were a decade ago, the constant changing of the rules brings with it major challenges to an industry already struggling to attract new customers.
Love them or hate them, emissions rules are redefining the motorcycles we ride. They can be tough for the manufacturers, bring issues to dealers and reduce choice for the rider. On the upside today’s bikes do less harm to the environment and, arguably, without such standards we may have been facing strong opposition to outlaw the internal combustion engine – and that’s a thought many of us could never comprehend.
Photos: Suzuki
