Will ethanol-blended fuel damage my motorcycle?

ethanol combine harvester large

Published on 7 July 2016 by Robert Drane

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Filed under Category: Tips and advice

No matter how fantastic your beloved bike is, it’s not going far without fuel - but what kind of fuel should that be? Mike Waters looks at what the future holds for your petrol tank.

There is a growing trend towards using biofuels like ethanol alongside more familiar petrol and, since oil supplies aren’t infinite, it looks like biofuels are here to stay. However, it’s not quite as simple as switching from petrol to ethanol without a second thought any more than making the switch between the horse and the motorcycle was a century back. There are significant differences that, while perfectly possible to manage and not likely to cause major changes at the pump, you nevertheless should be aware of if you want to continue enjoying riding in future.

What exactly is ethanol?

A combine harvesting a fieldEthanol is a contraction of ‘Ethyl Alcohol’ and is also known as ‘pure alcohol’, ‘grain alcohol’ or ‘drinking alcohol’. Chemically speaking, it is the exact same kind of alcohol you would find in any over-the-counter alcoholic beverage of your choice and it can also be readily found in solvents and modern mercury-free thermometers. Like oil-based petrol, it is a colourless liquid and has roughly similar safety requirements – throwing away a lit match around biofuels is just as dangerous as it would be with petrol or diesel.

In terms of production, ethanol can be distilled from grain, corn, wheat, cotton, barley, hemp, potatoes, sugar cane, sugar beets and so on, and the current extraction rate is about 1500 litres per acre of corn. This means that production can often be purely domestic and the need for a complicated system of ports, oil tankers and other transit headaches that international travel demands can be simply bypassed – with a subsequent impact on cost, security and stability of supply. On the other hand, it is less efficient as a fuel (the energy per unit volume ratio is 34 per cent lower than petrol) so you’ll likely end up using a fair bit more on a litre for litre basis.

What does this mean in practice?

An ethanol fuel pump in BrazilEthanol is already routinely blended into many petrol supplies and has been for years. In fact, the majority of petrol on sale in the UK is ethanol-blended. Internationally, the USA and Brazil have long been major players in ethanol-blended fuel and Brazil’s well-developed ethanol industry (which thrives on access to plenty of sugar cane) has been in place for decades now.

However, the current five percent maximum level mandated by the Renewable Transport Fuels Obligation is due to be raised to a 10 per cent maximum level (dubbed E10 and to be labelled Unleaded 95 E10) in accordance with the EU Renewable Energy Directive (RED) by the end of 2020, and that means the consequences of blending become greater too.

Will I be affected by E10 fuels?

95RON fuel pump That depends. There is currently no legal obligation for petrol companies in the UK to supply only E10 fuel – the choice still exists and the Petrol Retailers Association have told the BMF that E10 will be clearly labelled.

However, they do have to sell a significant proportion of their stock as renewable fuel and this will only be achieved by selling higher amounts of ethanol (which will almost certainly be E10).

What you may not know is that current 95RON petrol is actually E5 (i.e. five percent ethanol and 95 percent petrol) and this has been the case for several years. This means that E10 will be a doubling of the current ethanol content, which is less significant than replacing 10 per cent of fuel with ethanol outright.

Nearly all petrol vehicles currently on the road can happily use E5 and between 83 per cent and 92 per cent can use E10 – your manufacturer will be able to tell you whether your vehicle is compatible or not. If you are not sure, you will still be able to buy E5 for many years yet – although it may be the Super Grade option rather than the cheaper version. Also, these standards aren’t constant across all countries, so you’ll want to keep your eyes open when filling up abroad.

Will ethanol-blended fuels damage my motorcycle?

Close macro image of copperAs was mentioned earlier, ethanol is also a potent solvent. As a result, there is a significant risk of serious damage to aluminium, zinc, copper, brass, magnesium alloys, galvanized metals, seals, hoses, cork, fiberglass, rubber, polyurethane and epoxy resin – all of which can be found in the fuel systems of many classic bikes.

Exact numbers are difficult to come by, but the Department for Transport estimates that these side effects of E10 may affect as many as 8.6 million vehicles in the UK – of which as many as 750,000 are bikes.

Biker forums are awash with accounts of classic bike owners who fuelled up and were horrified to discover rapid and heavy damage to their fuel tanks and fuel systems. Fiberglass fuel tanks developing a network of pinhole leaks is a common problem and there are also an astonishing number of accounts of rubber seals around the necks of fuel tanks being broken down within just six months.

Similarly, accounts of cracked or corroded pipes throughout fuel systems are commonplace. This also leads to problems when anything that melts, corrodes or degrades anywhere along the way gets drawn into the engine.

It gets worse. Ethanol also has a high oxygen content, leading to faster rusting whenever it comes into contact with iron. This is compounded further by the fact that ethanol also absorbs water from the air too, leading to an octane-poor layer of fuel at the top of the tank and a less-than-ideal ethanol/water layer loitering at the bottom that can cause engine damage, poor running and difficult starts. On top of all this, some ethanol-blended fuels only have a shelf life of three months or less.

What is the future for ethanol?

The great debate over the merits of biofuels, the ramifications for pollution, side-effects on agriculture and the future of sustainability on the road is one we will be keeping an eye on. The exact future of ethanol-blended biofuels is too complicated to predict. However, what we can be sure of is that we are currently in a crossover period between technologies and that there will be a meaningful effect on both classic and current bike owners.

But it’s not all doom and gloom. Manufacturers have seen this coming for years and the overwhelming majority of bikes manufactured after 2000 are designed with ethanol-blended fuels in mind. Similarly, spare parts for classic bikes designed to prevent the potential effects of ethanol-blended fuels are available and, although new parts on an old bike isn’t really in the spirit of classic biking, you will still be able to keep your machine going. After all, to be doomed to obsolescence and never seeing the open road again by having the world just pass it by is a sorry end for a lovingly maintained classic bike.

Finally, this isn’t the first time there has been a significant shift in what kinds of fuel are available. The switch from Four Star to unleaded had its complications, yes, but the important fact at the end of it all is that the switch was made successfully. The world didn’t grind to a halt, we just had to pay a little more attention at the pump for a while. If that’s what it takes to keep our bikes on the road in an age of declining oil supplies meeting rising demand, fair enough.

A brief summary:
       • Greater level of ethanol in new 'E10' fuel
       • Serious risk of expensive damage for classic bike owners
       • Fuel systems and tanks especially vulnerable
       • As many as 750,000 bikes could be affected
       • Owners of pre-2000 bikes advised to take care
       • Efficiency changes could lead to much lower MPG

A quick history of ethanol fuels

Using alcohol as a fuel isn’t a new idea at all. Samuel Morey’s very first internal combustion engine prototype (or ‘Gas or Vapor Engine’, as he called it) all the way back in 1826 was fuelled on alcohol.

In more modern settings, there is plenty of technical experience of running on alcohol-based fuels out there – Speedway bikes run on ethanol, while ‘top fuel’ drag racers (both cars and bikes) and Indy cars run on closely-related methanol.

Using oil-based petrol in internal combustion engines on a mass production basis was deemed cheaper and easier than alcohol-based fuels by early inventors and petrol took off instead but, in our more environmentally conscious times, that state of affairs is changing.

This article originally appeared in the BMF's magazine, Motorcycle Rider.

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Images: Brazil ethanol fuel pump, author Mariordo Mario Roberto Duran Ortiz. Resized. Original available here under the Creative Commons Attribution 3.0 Unported licence. Macro image of copper, author Jonathan Zander (Digon3). Resized and cropped. Original available here under the Creative Commons Attribution-Share Alike 3.0 Unported licence. Speedway riders, author kallerna. Original available here under the Creative Commons Attribution-Share Alike 3.0 Unported licence. All other images Creative Commons CC0