What is E10 fuel and is it safe for your bike?

The Government has announced that it wants to adopt E10 petrol – with 10% ethanol content – as the standard grade on UK forecourts in 2021 but it’s a move that could impact huge swathes of the motorcycling community.

Announcing a new consultation on plans to replace the current normal ‘premium unleaded’ with a higher-ethanol E10 formulation, Transport Secretary Grant Shapps said: “The next 15 years will be absolutely crucial for slashing emissions from our roads, as we all start to feel the benefits of the transition to a zero-emission future.

“But before electric cars become the norm, we want to take advantage of reduced CO2 emissions today. This small switch to petrol containing bioethanol at 10% will help drivers across country reduce the environmental impact of every journey. Overall this could equate to about 350,000 cars being taken off our roads entirely.”

It’s clear from his words, and from the consultation document itself, that the Government’s focus is purely on cars, with little or no thought to the impact that such a change will have on motorcyclists.

What is E10 fuel?

At the moment, standard ‘premium unleaded’ (the ‘premium’ tag is a hangover from the days when lower-octane fuels like two-star were still available) is actually ‘E5’, which means it’s gasoline that’s allowed to be mixed with up to 5% ethanol – which is simply alcohol under another name.

The proposed E10 fuel, which is already offered in some European countries and the USA, increases the allowed percentage of ethanol to 10%. Because ethanol is a renewable fuel, made from crops rather than distilled from crude oil, and reduces CO2 emissions, it’s seen as greener than purely oil-derived petrol formulas.

How much would E10 fuel reduce emissions?

According to Government figures, the existing E5 fuel reduces UK road transport CO2 emissions by 888,000 tonnes per year (2018 figures), and moving to E10 could cut another 700,000 tonnes of CO2 emissions per year.

The same document gives the impression that E10 is vastly better than normal petrol, saying: “Using bioethanol in place of fossil fuels can reduce CO2 emissions by around 65% for an equivalent volume of fossil fuel.”

Impressive though they sound, the numbers don’t actually give any perspective. So let’s try to add some here:

• CO2 emissions from UK transport in 2018 totalled 121.4 megatonnes in 2018. That’s 121,400,000 tonnes. As such, if E10 could cut emissions by the maximum 700,000 tonne figure that the Government quotes, it will equate to a reduction in transport-based CO2 emissions of less than 0.6%. And of course, transport only accounts for a fraction of CO2 output. Government estimates put the UK’s total at 364.1 million tonnes in 2018, which means a 700,000 tonne reduction represents a reduction of less than 0.2%.
• Taking other greenhouse gas emissions into account, the UK’s total output was equivalent to 448.5 million tonnes of C02 in 2018. That means that even with the best possible reduction associated with E10, it could only lead to a reduction of around 0.15%
• Looking at the statement: “Using bioethanol in place of fossil fuels can reduce CO2 emissions by around 65% for an equivalent volume of fossil fuel,” the key part is the second half of the sentence: equivalent volume. Since E10 only increases the maximum ethanol volume by 5% over existing E5 fuel, its best possible reduction compared to the status quo is 65% of 5%, which is 3.25%.

While it’s true that every little helps, it’s worth noting that those numbers don’t take into account any CO2 emissions that might be associated with the growing, harvesting and production of ethanol, either.

On top of that, there’s the issue of fuel consumption. E10 fuel contains less energy than the same volume of E5 or pure petrol, and as a result engine’s burn more of it to achieve the same performance. Lab tests have shown that E10 increases fuel consumption by an average of 3% compared to current E5 fuels, and a test by What Car magazine in 2014 discovered fuel consumption rose by as much as 10% on some vehicles.

The Government’s own impact statement doesn’t put the figures that high, but it does note that costs will rise, saying: “Introducing E10 will add to fuel costs paid by motorists. Moving from E5 to E10 is estimated to reduce pump price petrol costs by 0.2 pence per litre. However, as the energy content of the fuel will also decrease, motorists will have to buy more litres of fuel. Overall fuel costs for petrol cars are therefore estimated to increase by 1.6% as a result of moving from E5 to E10.”

Of course, any percentage increase of money spent at the fuel pumps will see a corresponding growth in tax revenues for the Government. Fuel duty revenues at the moment stand at £28 billion per year, or 1.3% of national income, so even a small increase in petrol usage adds up to a significant tax windfall for the Government.

What are the problems with E10 fuel?

Even if the emissions benefits are relatively minimal, a switch to higher ethanol content petrol could still have benefits. After all, ethanol is renewable and the UK’s own billion-pound bioethanol production industry is currently operating below its potential capacity, so jobs in the industrial and agricultural side could be secured by using more of it.

However, adding it to petrol doesn’t come without a price, both figuratively and literally.

Ethanol might mix with petrol and burn, but there’s no guarantee that every bike will be able to use an E10 mix. The current E5 standard was adopted because it was considered that a 5% ethanol ratio was the maximum that engines and fuel systems designed for conventional petrol could safely deal with. Rising above that figure brings risks, particularly to older vehicles.

The Government’s own consultation document says “…vehicle compatibility has been the main barrier to the introduction of E10 so far. Not all vehicles have been approved by their manufacturers for use with fuel with more than 5% ethanol. This is because higher blends of ethanol can cause corrosion of some rubbers and alloys used in the engine and fuel systems of some older vehicles.”

It goes on to dismiss the problem by focussing on people’s everyday cars and saying that as they’re scrapped and replaced with newer models the problem will diminish. The document says: “While there are currently around 400,000 cars that fit the description, this figure is expected to halve by 2021. At that point, these vehicles will represent less than 1% of the total car parc.”

You’ll notice there’s no mention of motorcycles, and that’s the issue.

Among the problems with ethanol is the fact that it prefers to burn at a different air/fuel ratio than petrol. On a vehicle with fuel injection, a three-way catalytic converter and a lambda (oxygen) sensor in the exhaust, that’s not necessarily a problem, since the exhaust sensor can tell the fuel injection to compensate. Most cars have had such kit for the last 20 years, but on bikes emissions laws have been slower to catch up, so many didn’t adopt the same technology until around 2010. Since the average bike in the UK is 14.7 years old, a vast number come from the days before manufacturers had considered the use of ethanol fuels.

That’s not E10’s only problem, either. Ethanol is hygroscopic, which means absorbs and mixes with water, even drawing it in from the air around it. That’s one of the reasons it can cause corrosion, since it means parts of fuel systems that were never designed to be in contact with water are suddenly exposed to it. On top of that, ethanol is a solvent and that means rubber, plastic and fibreglass parts that were designed to be in contact with pure petrol can melt once exposed to E10. Since many bikes have plastic fuel tanks, that’s a worry. A few years ago, there were issues in America – where E10 has been in use much longer, with bikes including Ducati Monsters, Sport Classics and Multistradas suffering distorted plastic fuel tanks as they reacted to ethanol in the fuel.

How else can E10 fuel cause problems for my bike?

Although the water-attracting properties of E10 aren’t necessarily a massive problem if you’re constantly using a vehicle and running through tanks of fuel, they can be amplified when a vehicle is left unused with petrol in the tank.

That’s a particular issue for bikes, since many are either laid up over winter or used sporadically with long idle periods. During that time, E10 has a reputation for going stale and undergoing ‘phase separation’ when vehicles aren’t used. That means the ethanol falls out of solution with the petrol as it absorbs more water. The result could be an engine that won’t start until the fuel is replaced, and some suggest this phase separation can take place in as little as three months.

Is there any petrol without ethanol?

There was, though it depended where you lived. Esso Synergy Supreme+ 99 premium petrol was ethanol-free, except in Devon, Cornwall, North Wales, North England and Scotland, but the messaging on its website changed in 2023 and it appears that the option of ethanol-free fuel is being fully phased out.

While legislation requires the pumps to be labelled as E5, this is to indicate that it’ll deliver ‘up to 5% ethanol’, which means it includes those with no ethanol.

Esso’s website stated that ‘There’s currently no requirement for renewable fuel, like ethanol, to be present in super unleaded petrol although this could change in the future, in which case we would comply with any new legislation.’

To find your nearest Esso station, click here.

What if my bike isn’t compatible with E10, but there’s no Super at the pump?

We asked Kawasaki, Yamaha, Honda, BMW, Suzuki, Royal Enfield, Ducati, KTM and Harley Davidson for their recommendations, and here’s what we’ve heard back so far…

Kawasaki explained that the exact parts that could be affected in older bikes that aren’t compatible isn’t readily available, but that if a rider had to put a tank-full through their bike, it shouldn’t be a big problem, as long as it wasn’t left in for a lengthy period.

Royal Enfield said that its products have been commercialised in countries where the percentage of ethanol can go up above 27% (for instance Brazil), and that it has no major impact on the durability of the components used, however it can’t declare any of its Euro III and before products as ‘E10 sustainable’ as they weren’t homologated for it at that time.

BMW pointed out that “All current BMW Motorrad motorcycles, and all of those developed in previous years, have been engineered to operate using E10 fuel without technical problems” but that owners must use the specified fuel octane grades (eg 95 or 98 RON).

Yamaha was the only other company to respond to our request, and sent some very useful information relating to both its motorcycle and outboard engines. Overall, using E10 in an E5-only bike should be avoided as nobody can know the condition of the parts in your engine (we’ve all seen how cracked carb intake rubbers can get) with age, so running E10 could be the last straw for something inside. However, if you need to get home and there’s been another spate of panic buying leaving little to choose from, you might want to consider putting in the minimum of fuel, then topping up as soon as possible with super before getting that running through the system.

How do I store a bike with E10 fuel?

If your bike isn’t compatible with E10 fuel then only store it with super unleaded, and keeping the tank completely full will minimise any corrosion that could occur. If, on the other hand, your motorcycle is fine with E10, you still shouldn’t leave it to stand for too long – Yamaha points out that ethanol has just a six-week shelf life, the octane then beginning to decrease, which is a problem in bikes (and boats) that are used infrequently or stored over winter.

Yamaha recommends regularly using a quality fuel system cleaner and a fuel stabiliser when storing a motorcycle for any period of time in order to prevent deterioration. It even goes on to suggest removing fuel from the tank altogether (and, presumably, the fuel system) when storing for extended periods.

That’s not always practical, so our best advice is to use the bike as much as possible – run it regularly, but better still get it out for a ride as much as you can to keep the fuel moving through the system.

And while your bike might be compatible with E10, if you’re not going to use it as much for a while (for instance over winter), get it as low as possible on your last ride, then fill up with super unleaded.

The general consensus is to keep the tank brimmed, and some even suggest blocking the fuel tank breather to restrict any moist air getting to the fuel, though this is easier on older bikes and make sure you leave a note on the tank to remove it before you next ride, or you’ll wonder why the bike stalls.

Can I do or add anything to the fuel to help it?

While some might consider removing the ethanol from fuel, ­­this isn’t recommended. Yamaha explains that if relying on phase separation, where the ethanol (and water) molecules settle to the bottom of the liquid (usually in your tank), the remaining gasoline will have a lower octane rating that may well be below that required by the engine. In its marine workshop technical data, Yamaha states that leaded gasoline should not be used as it can seriously damage engines, so adding a lead replacement product to your fuel could be risky.

BikeSocial is running a test of stabilisers to see if any help protect the fuel, so be sure to keep an eye on our homepage…

Octane vs energy

Ethanol has a higher octane rating than petrol, which might lead you to think that more of it will lead to a power boost. But sadly, that’s not likely to be the case.

While the term ‘high-octane’ is synonymous with speed and excitement, and pure ethanol has a rating of 108 RON (Research Octane Number), that doesn’t mean that E10 fuel will have more energy than existing unleaded. In fact, quite the opposite.

Octane affects how fuel burns rather than how much energy it produces. A higher octane rating means a fuel that will burn in a more controlled way and at a lower temperature, which is good for high performance engines as it allows higher compression ratios or more boost to be used. But while ethanol is high octane, its energy density is lower than gasoline. Where petrol has an energy density of 34.2 MJ/L (megajoules per litre), ethanol’s is only 24 MJ/L. E10 petrol’s rating is 33.18 MJ/L, so notable lower than ‘pure’ petrol’s.

Ethanol’s higher octane could be used to make engines better, but you’d need to design the engine specifically to achieve that – with a higher compression ratio or increased turbo boost to take advantage of its higher octane rating and its combustion chamber cooling properties. The Koenigsegg CCXR supercar makes 20% more power on E85 (85% ethanol fuel) than it does on normal gasoline, but it’s designed to do that, with different injectors, fuel lines and piston rings as well as increased supercharger boost pressure. On the downside, the lower energy density of E85 means the CCXR guzzles more of it than the gasoline drinking Koenigsegg CCX version.

Without making mechanical changes to maximise performance from the higher octane of ethanol, you’re left only with its lower energy density, giving less performance and worse economy.

How do I know if my bike can used E10?

For newer bikes, E10 shouldn’t be a problem. It’s been used as a standard fuel during EU test procedures since 2016, so anything made more recently than that is likely to be fine.

The European Motorcycle Industry Association, ACEM, some years ago asked its members which models are compatible, and we’ve included that at the bottom of this page.

For a more comprehensive service, the Dutch website e10check.nl provides a search function to check what models can or can’t use E10. Unless you’re fluent in Dutch you’ll probably need to run it through Google Translate, but it’s a valuable resource, nonetheless.

What if my bike can’t run E10?

Although the Government hope to introduce E10 as the new standard in 2021, there is still a consultation period before that happens. That means there’s a chance for everyone to have a say by completing a response form on the Government website here, where you can also download the full consultation document and the impact assessment.

However, with strong environmental and industry backing for the adoption of E10, and the vast majority of car drivers being largely unaffected by the change, it’s likely that it will become the new ‘standard’ fuel in the place of the current premium unleaded.

The consultation paper says: “At present, the main barrier preventing suppliers from introducing E10 is that there are some petrol vehicles which are not approved for E10 use. Consequently, consumers need to be informed in a coordinated manner and be fully engaged with the change. In addition, the provision of E5 needs to be guaranteed for those vehicles not approved for E10 use.”

While one option is to allow petrol stations to stock E5 alongside E10, that isn’t likely to be taken up. In Germany, where both fuels are offered, just 10% took up the E10 option. Such a move would also be a hurdle for fuel stations that don’t have enough pumps or underground tanks to add another type of fuel to their offerings.

Instead, it’s likely that anyone who either can’t use E10 or doesn’t want to take the risk will have to cough up for more expensive super unleaded, which will remain at the E5 ethanol level.

The consultation paper says: “We recognise that some motorists, particularly owners of classic and cherished vehicles, would still need access to E5. For that reason, this consultation is also proposing to require that that the higher octane "super" grade, available at many filling stations, remains E5. This means petrol with a lower ethanol content would still be widely available after E10 is introduced.”

With super unleaded currently costing around 12p per litre more than normal, ‘premium’ unleaded, that means a typical 16-litre tankful would cost around £2 more for every fill-up.

ACEM’s E10 compatiblity list:

BMW Motorrad

All models are compatible with E10. However, the number of octanes needs to be compatible with the model according to user handbook.

BRP

All models belonging to the L-category are E10 compatible.

Ducati

Ducati Desmosedici 990 RR, Vehicles registered as from 18/05/2007

Ducati Diavel 1198, Vehicles registered as from 27/10/2010

Ducati Diavel 1198 ABS, Vehicles registered as from 27/10/2010

Ducati Diavel 1198 Diavel Carbon, Vehicles registered as from 27/10/2010

Ducati Diavel 1198 Diavel Carbon ABS, Vehicles registered as from 27/10/2010

Ducati Hypermotard 1100, Vehicles registered as from 15/02/2007

Ducati Hypermotard 1100 evo, Vehicles registered as from 02/07/2009

Ducati Hypermotard 1100 evo SP, Vehicles registered as from 29/09/2009

Ducati Hypermotard 1100 S, Vehicles registered as from 15/02/2007

Ducati Hypermotard 1100 S+, Vehicles registered as from 02/07/2009

Ducati Hypermotard 1100+, Vehicles registered as from 02/07/2009

Ducati Hypermotard 796, Vehicles registered as from 02/07/2009

Ducati Monster 1100, Vehicles registered as from 10/07/2008

Ducati Monster 1100 ABS, Vehicles registered as from 14/10/2009

Ducati Monster 1100 evo ABS

Ducati Monster 1100 S, Vehicles registered as from 10/07/2008

Ducati Monster 1100 S ABS, Vehicles registered as from 14/10/2009

Ducati Monster 659

Ducati Monster 659 ABS

Ducati Monster 696, Vehicles registered as from 15/01/2008

Ducati Monster 696 ABS, Vehicles registered as from 14/10/2009

Ducati Monster 796, Vehicles registered as from 04/02/2010

Ducati Monster 796 ABS, Vehicles registered as from 04/02/2010

Ducati Multistrada 1200 , Vehicles registered as from 04/12/2009

Ducati Multistrada 1200 ABS , Vehicles registered as from 04/12/2009

Ducati Multistrada 1200 S Pikes Peak Special Edition

Ducati Multistrada 1200 S Sport , Vehicles registered as from 04/12/2009

Ducati Multistrada 1200 S Touring , Vehicles registered as from 04/12/2009

Ducati Streetfighter 1098 , Vehicles registered as from 12/01/2009

Ducati Streetfighter 1098 S , Vehicles registered as from 12/01/2009

Ducati Superbike 1098 R Corse , Vehicles registered as from 30/10/2007

Ducati Superbike 1198 , Vehicles registered as from 03/09/2008

Ducati Superbike 1198 SP , Vehicles registered as from 03/09/2008

Ducati Superbike 848 evo , Vehicles registered as from 20/05/2010

Harley Davidson

All Harley-Davidson models from Model Year 1980 are compatible with E10 fuel.

All models before this model year should use RON 98 fuel.

Honda

All Honda motorcycles and mopeds produced for the EU market since 1993 can use ethanol-blended gasoline up to 10% although carburettor-equipped models could experience poor driveability in cold weather conditions.

Kawasaki

E10 fuel compatible Kawasaki motorcycle models:

Kawasaki model - Model year (and onwards)

KLX125 - 2010

D-Tracker 125 - 2010

KLX250 - 2008

Ninja 250R - 2008

Ninja ZX-6R - 2007

ER-6n - 2006

ER-6f - 2006

Versys - 2007

Z750 - 2007

W800 - 2011

VN900 - 2006

Z1000 - 2009

Z1000SX - 2011

Ninja ZX-10R 2006

ZZR1400 - 2006

1400GTR - 2008

VN1700 - 2009

VN2000 - 2008

KTM

KTM motorcycles and ATVs are compatible with E10 from model year 2000 onwards.

Peugeot Scooters

All Peugeot Scooters from model year 2000 are E10 compatible.

Piaggio

Most models over 50cc belonging to the Piaggio Group are compatible with E10 from 1.1.2011 onwards. Piaggio does not recommend use of E10 on Mopeds (i.e. 50cc) currently in production [at the time this list was made].

Royal Enfield

All Euro IV bikes onwards are declared E10 compatible as per homologation

Suzuki

2002 Model Years and onwards - all motorcycles can use E10 with no problems.

1992-2001 Model Years – some models can use E10 fuels and some models cannot. The user should contact his national importer for clarification.

1991 Model Years and earlier – RON 98 (no bio-fuel content) must be used.

Triumph

All models, starting from Model Year 1990, are compatible with E10.

Victory Motorcycles

All Victory motorcycles can use gasoline that has been blended with up to 10% ethanol (E10). Check fuel’s octane rating for compatibility with the vehicle according to the owner’s manual.

Yamaha

All Yamaha models from Model Year 1990 are compatible with E10.