Euros 95 has disappeared. To save the planet, it has been replaced by E10. It contains up to 10% bioethanol. Horror stories are all over the Internet. Cars and motorcycles break down, if you don’t use them for a couple of weeks they won’t start anymore. True or myth? And why bioethanol?

By Peter Aansorgh, (copyrights Peter Aansorgh Producties)

When the oil sheikes of Kuwait closed the oil tap in 1973, we discovered just how much we depended on oil. In those days the ”Club of Rome” published a report that stated we would run out of oil in about 30 years. Now, 41 years later, we still use petrol and diesel. The club wasn’t entirely wrong, though. Insights and technology change. And sometimes new oil reservoirs are discovered, like 10 years ago, when a huge amount of oil was found underneath the North Pole.

More possibilities

In the last 40 years new methods like Enhanced Oil Recovery where developed to win more oil from wells. Before, an oil well was considered depleted when about a quarter of the oil was won, because at that point the oil wouldn’t flow out anymore. With advanced steam injections these wells got a second and even a third life. That increases the amount of oil you can win from a well considerably. So, we will still have oil for decades to come. Methane gas will also be available for 250 years at the current consumption rate. Adding to that are alternative sources, like oil from sand fields or oil from coal. Then there’s fracking, another technology to win gas and oil from the earth. However, it’s not just a matter of technical possibilities, but also of social acceptability. Oil and coal produce CO2-emissions, nuclear energy produces radioactive waste, windmills pollute the horizon, fracking destroys the top layers of the soil. What counts is how the society thinks about a certain form of energy at a certain moment. A good example is oil sand winning. People don’t like it, because the open mines would destroy nature. It is, however, possible to redesign these environments afterwards, even to nature reserves.

Het verbranden van benzine voegt CO2 toe aan de atmosfeer, het verbranden van bioethanol niet

Global Warming

Oil will be available for a couple of decades to come. But there are more challenges, like global warming, a problem that is caused by excessive CO2-emissions. Not everybody believes that, though. Some people think that the temperature rise on earth is a natural fluctuation. We have had several ice ages, with warmer periods in between. The icecaps in the Netherlands disappeared 10,000 years ago, long before the Industrial Revolution. So, there have always been fluctuations in temperature. However, the vast majority of scientists believe that the current, vast rise in temperature is caused by human CO2-emissions, a consequence of ever-increasing combustion of fossil fuels. The man-made CO2-emissions are 4% of the total CO2-emissions, the road transport causes 20% of those 4%.


CO2 or carbon dioxide absorbs infrared radiation, created by sunlight reflecting on the earth. The carbon dioxide traps the infrared radiation, a process which acts like a greenhouse. So, it gets warmer. Between 1880 and 2012 the temperature on ground level has risen by about 0.85°C. That doesn’t seem like an awful lot, but the consequences are big. The icecaps melt further, the water level rises. Not only because of the melting water, but also because water expands when it heats up. 0,00021 m3 per m3 per degree Celsius. And as there is 1,300,000,000 km² of ocean water, that ads up. So, for every degree Celsius we get an extra 273,000 km³ of water extra. That means more floods and the need to heighten dykes. Another effect is that winters are getting softer and that the weather becomes a bit wilder because of the high concentration of CO2 in the atmosphere. Water also absorbs CO2, which means a part of the carbon dioxide dissolves in the seas and oceans. The acidity of the water increases which kills water plants, coral and sea animals. The dead zones in the oceans are increasing rapidly.

Cutting CO2

Scientists believe we should limit the CO2 concentration in the atmosphere below 450ppm-equivalent to reduce the effects of global warming to 2°C in the year 2100. To obtain that, CO2 output must be reduced by 37% by 2030. All sectors must contribute to reach that goal. There are no demands for motorcycles, but for cars there are limits: this year, 2020, the average emission of new cars must be reduced to 95 g CO2 per kilometer, which is a reduction of 40% compared to 2006. As of 2030, this amount should be further reduced by 35%. From 2035 all new cars should be electric too, which only helps if they use electricity from renewable sources, not from oil or gas. For now, it’s also a big problem that the number of cars worldwide is growing very fast, because of the improving welfare in upcoming economies like India, China, Russia and Brazil. That sparks the growth of mobility. It is estimated that the amount of passenger cars will double from 1 billion to 2 billion cars in the next decades. The world wide fuel consumption will rise and with that, the CO2– emissions. Other estimations state that autonomous cars will change mobility and that the number of cars will be reduced by 50%, because people will use our sharing platforms and cheap autonomous taxis.

Efficient fuels

the question is, whether you can reduce the CO2-emissions by using higher quality fuels. CO2-emissions largely depends on the amount of fuel you use. You can try to be efficient with it, but that’s the task of engine designers, who have to increase efficiency. It is possible to support the combustion process with high quality fuels though. Therefore, premium fuels have dopes that keep injectors and combustion chambers clean, to keep the combustion process as efficient as possible. They also feature dopes to decrease friction. High quality fuels can therefore reduce fuel consumption by 2%.

Cleaner fuels

CO2-emissions aren’t the only problems of the combustion process. There’s also CO, HC and particles (soot). They reduce air quality in big cities. Better fuel quality can improve that. So, for has been taken out of fuel ages ago. You can also improve fuel by producing them synthetically by Gas to Liquid. In this process, you make a fluid fuel by coupling methane gas molecules to another. A synthetic fuel therefore has less impurities then a mineral fuel. That’s just a bunch of components, distillated from crude oil based on their boiling points. The good and the bad together, because they share a boiling point. Without the bad components there will be a better, more complete combustion with less CO, HC and soot emissions. An improved combustion will also reduce noise, up to 3 dB. It is an expensive process though; it also takes energy to make fuel by Gas to Liquid. So, it remains a trade- off.

ethanol or alcohol is a clear fluid


One way to reduce CO2-emissions, is to use biofuels. At this moment, up to 10% bioethanol is mixed with petrol. Of course, bioethanol is a hydrocarbon, just like petrol. So, they both produce CO2 when you burn them. But petrol is made from crude oil, bioethanol from plants. Plants absorb CO2 out of the atmosphere and create hydrocarbons. Burning those, creates a circular system. The change from 5% to 10% bioethanol presumably leads to 2% less CO2 output. However, growing plants, harvesting them and turning them into biofuels takes energy and produces CO2 too. Besides that, artificial manure is often used to grow the plants. This emits N2O into the atmosphere and that’s worse than CO2. The global warming potential of N2O is 310 times worse. Another question is, whether it’s socially justifiable to turn food supplies into fuel when half the planet is hungry. Destroying the last bit of rain forest to create room for growing plants for biofuels doesn’t seem like a very good idea either. That’s why scientists are developing a second-generation biofuel from rest products like wood chips, blunt residues and used frying oil. There are even experiments for a third-generation from algae. Our bioethanol comes mainly from grain and sugar beets. So, you could wonder whether there’s any point in using it to reduce CO2.

Most motorcycles don’t run very well on E10. If you can’t get Euro 95-E5, you’re better of with a premium fuel without bioethanol..


Now, on itself, bioethanol isn’t a bad engine fuel at all. It Road Octane Number is 108. So, it is less likely to detonate than petrol (Euro 95) or even premium fuel, which Road Octane Number is 97 or 98, depending on the brand. If you would build an engine specifically for bioethanol, then you could choose a higher compression ratio. A higher compression ratio gives a better fuel efficiency because the thermodynamic efficiency of an engine largely depends on this ratio. In your existing car or motorcycle, the compression ratio is fixed. You can’t adapt it, so the high octane-number doesn’t do anything for you. Also, you’re not riding on pure bioethanol. E10 is not euro 95 with extra bioethanol either. It’s the newly developed petrol, containing up to 10% bioethanol. Manufacturers ad methyl-tert-butyl ether to increase the octane number to the desired value. That’s no different when manufacturing E10. So, the Road Octane Number of E10 is also 95, like before. Many fuel stations even call it Euro 95 – E10.

Energy density

As a fuel, ethanol contains less energy than petrol. If you would use pure ethanol, you would have to inject 1.5 times as much fuel to get the right mixture and the same energy production. Of course, this effect is a lot smaller when you at only 10% ethanol to petrol. The modern injection engine can adjust the mixture, but if you have to inject more fuel for every combustion, the fuel economy will go down. Older engines with carburetors have bigger problems: they can’t compensate. As a result, they will run a leaner mixture, which is especially problematic for the last generations of carbureted engines, that already run leaner mixtures due to the sharper in mission standards. They will overheat, lose power and as a result the fuel economy goes further down. I tried E10 on motorcycles quite often, when touring in France. Both injection engines as carburetor engines use about 15% more fuel when using E10. You can also sense more vibrations in the engine.


There are more disadvantages to using ethanol. For starters, it’s pretty aggressive and corrosive. It damages some sorts of rubber, polyester, fiberglass and certain alley medium alloys. So, you’re in for a world of trouble if you’re fuel system is built with these kinds of materials. There’s more trouble for two-stroke engines, as ethanol and two-stroke oil mix very well with petrol on their own, but not together. That’s bad news for older two-stroke engines, that use premix. The oil will separate in your tank, so your engine risks getting fuel without oil. Without lubrication, the engine will seize.


The most important question is, is your fuel system made from ethanol-resistant materials? Most, still road going vehicles were manufactured after 2000, so they are made for Euro 95. That contains bioethanol, so it can handle that, it should be able to withstand E10 too. However, there are always exceptions to the rule, as the Opel Signum proves. There’s a Dutch website to check if your vehicle is E10-proof: It will tell you that the Opel/Vauxhall 2.2 L Signum engine isn’t. Is it a disaster if it isn’t? Of course not, because fuel stations are still allowed to use premium fuels without bioethanol. According to the manufacturers, BP Ultimate, Shell V-Power, LUK superplus en Esso Synergy Plus 98 doesn’t contain bioethanol, even though it’s called E5 too. At least, in the Netherlands… Some premium fuels, like Total Exellium, do contain bioethanol. It is also called E5. Governments are always good at creating confusion. E5 can contain up to 5% bioethanol, but it doesn’t have to. So, this branding is pretty useless.

Storage and contamination

There’s more trouble: fuel with bioethanol ages quickly, because ethanol attracts water. That leads to sludge, lacquer and other contaminations in the fuel system. Fuel jets and injectors get contaminated, flowed needles of carburetors stick in their seats, carburetors start to leak. The water/ethanol mixture can separate and sink to the bottom where it creates an acid liquid at the bottom of your tank or carburetor. Your tank starts to rust and there will be oxidation in your carburetor or injectors. Engines will start badly, tick over irregularly and even cut off. With euro 95, these problems often occur after more than 60 days of storage. You can expect these problems to occur sooner with E10. When storing your car or motorcycle, you will experience another problem: the lighter fractions in your fuel will evaporate slowly. The remaining, heavier fractions do not evaporate as well, so your engine won’t start as easy as it used to. The octane number also decreases in time, so the 95 RON fuel can be a 92 RON fuel after the winter.

Ethanol ages quickly and contaminates injectors. They wil not atomise the fuel very well anymore.

Dopes and storage fuel

If you own an old-timer or a motorcycle you rarely use, you’ve got a couple of options: You can top up the last two tanks before you put your vehicle in storage with a premium fuel that doesn’t contain ethanol. In the last thank you can at a conserving additive, like Forté MotoPower II, Eurol Fuel Treat or Liqui Moly Petrol stabilisor. These additives stabilize the fuel, absorb condensation, clean your fuel system and notarize acids. Some workshops will add these additives to your fuel system when servicing your car or motorcycle, to maintain your fuel system and optimal condition. If needed, you can restore the Road Octane Number of your fuel with Eurol Petrol Octane Improver or Liqui Moly Octane booster.

fuel system cleaners keep your fuel system in top condition

Storage fuels

Aspen is an alternative for premium fuel with dopes. It’s the synthetic alkylate fuel. It doesn’t contain aromatics and it burns colorless, odorless and without toxic fumes. It’s highly popular in the world of greenhouses and chainsaws, were people are directly exposed to the exhaust gases. It is good stuff and seems to be perfect for storing old-timers or motorcycles. That, however, is only true if the engines are new or newly restored and never run on regular petrol. That’s because aromatics in petrol penetrate gaskets and seals. Other result, they swell. If you replace petrol with Aspen, the aromatics will retreat from the gaskets and seals. They will shrink again and that will cause leakage. You can only use Aspen if you never change to regular petrol and back. The road octane number is 95, so it isn’t really suitable for high-performance engines either.

For old-timers and motorcycles there are special storage fuels, like Ecomaxx.  It is also a synthetic alkylate fuel, but it has been adapted for cars and motorcycles. Regular fuel is a mixture of components derived from crude oil, based on their boiling point. Alkylate fuel is produced synthetically, comparable to gas-to-liquid. So, it is very pure. Ecomaxx produces several specialized fuels for old-timers, for motorcycles, for boats or for dirt bikes. Ecomaxx offers 98 RON and 92 MON (Euro 95’s MON is only 85). More importantly: it has a shelf life of 3 to 5 years. It does contain aromatics, so seals and gaskets remain swollen and do not leak. Ecomaxx is about €3.35 per liter so it’s quite an investment. Still it’s much cheaper than dismantling your fuel system and cleaning it ultra-sonic.

Ecomaxx is a storage fuel with a shelf life of about 5 years.

Old-Timers and two strokes.

Alkylate fuel burns cleanly. It doesn’t leave deposits on valves or pistons and you can hardly smell it. The lack of smell is very important for classical cars, to strokes and mopeds. When people see or smell exhaust fumes, they will start protesting and before you know it, you’re not allowed to drive your old-timer anywhere. Smoke and smell are caused by unburnt petrol. All timers were designed for less strict emission standards – if any – and will usually run the richer mixture for better acceleration, protection of valves and smooth idling with the technology of yesteryear. On two strokes, the free flow from port to port when the piston is on bottom dead center is also a cause of unburned fuel, as fresh mixture can flow directly into the exhaust.

That’s problematic, as petrol contains about 35% aromatic hydrocarbons. Of that, 0,5-0,9% is benzene, 3–15% is toluene. Those are cancerous substances which freely evaporate into the air. Ecomaxx only contains 10% aromatic hydrocarbons and hardly contains any benzene or toluene (< 0,1%). Due to the pure composition and burns better and it produces 40% less smoke causing components. You can hardly smell Ecomaxx fuel, you don’t see smoke from the exhaust and you hardly smell exhaust fumes. I personally tried it in a 1971 two-stroke Puch MS50V moped. It works! There is, by the way, a special premix two stroke Ecomaxx fuel

E10 and two stoke oil don’t mix. There are synthetic storage fuels that do.

Not a disaster

If you own a modern car or motorcycle and you never leave it alone for a couple a month, you will have no problem running it on E10. If you own an old-timer or if you leave your vehicle and used for longer periods of time, you can find enough premium fuels at the larger fuel stations. For storage, you can find dopes and special storage fuels. So, E10 is certainly not a disaster!

DID YOU LIKE MY ARTICLE? Then I would apriciate it if you would buy me a cup of coffee. You can donate a little something by clicking the “donatie” button in the menu bar. All donations are apreciated!