Honda CBR 250 Forum banner
1 - 2 of 2 Posts

878 Posts
Discussion Starter · #1 ·
For those that are interested, especially those with vintage bikes here's a letter from and oil company representative sent in response to a queery from an owner of vintage cars regarding fuel issues. It was posted on a W650 forum I follow based in the UK.


In answer to your question yes petrol fuel does contain upto 5% ethanol as a
bio component which undoubtedly cause issues with rubber components and seal
and things such as fibreglass fuel tanks in aviation. This is a government
legislative requirement known as the renewable fuels transport obligation
(RTFO) which was on introduced on 1st April 2009 in the UK, and as
consequence covers all forecourt fuels of all manufacturers and requires
their fuels to contain an aggregate of 5% Bio content which is Ethanol in
petrol fuel and FAME (Fatty Acid Methyl Ester) in Diesel Fuels.
There will be no liability with the fuel manufacturer as all our petrol
fuels comply with the BS EN 228 which allows upto 5% ethanol content in
gasoline fuel. All major manufacturuers have tested fuels upto 10% without
issue. In terms of vintage cars, there are currently no fuels available
which meet the exact specification that the engines were originally designed
for, so it is very much incumbent on the consumer to ascertain that the fuel
they are suing is 'fit for purpose'

The Issues you raise are certainly real issues for vintage car owners. The
fuel we sell will continue to comply with the relevant fuel standards and
specifications as it did previously. The finished petrol will meet the UK
gasoline standard EN228, and the maximum amount of ethanol blended into the
fuel will be in line with this and the RTFO (renewable fuel transport
obligation - 5% max). However that doesn't really help owners of vintage
vehicles. There are several things you can do to minimize the effects of
ethanol. Firstly run a non-alcohol based fuel stabilizer all year round. As
you say, older engines were designed primarily for straight gasoline, and
using ethanol without protection may cause corrosion of some metals in the
engine. It also may damage natural rubber and cork parts. Fuel stabilizers
(I believe Stabil do a product) contain additives to protect against rust
and corrosion caused by ethanol fuel blends. If practical install a water
separation filter and fuel filter, and replace fuel lines, gaskets or
o-rings with new ethanol resistant materials. Similarly replace the fuel
tank if necessary with one made from an ethanol resistant material.

In terms of laying up the vehicle; Assuming the above measures are in place
(I cannot make a laying up procedure if they are not, as it simply would not
be advisable with fuel containing ethanol), I would suggest filling the fuel
tank to about 95% of its capacity with fuel, rather than leaving the fuel
tank low. This minimizes; the tank-breathing effect, the loss of volatile
components and the ingress of moisture into the fuel tank. The later in
extreme cases can cause the appearance of free-water in the fuel.

If a fuel is to be stored in a motor vehicle fuel tank, then maintaining
fuel quality is important in order to maintain good start-up and a good
level of vehicle drivability. When an engine fails to start after a period
of lay up, it may be less to do with fuel deterioration, and could be
related to un-seasonal fuel, which may not be sufficiently volatile to start
the engine from cold. Non volatile residues are often observed in the fuel
tank, delivery system and/or carburetors in cases of severe evaporative loss
of a gasoline. The reside can manifest itself as either a gum or
lacquer-like film or deposit, or a gel-like substance. This residue would be
a combination of low-volatility constituents and detergent additives that
are found in gasoline, but concentrated after evaporation. We do not advise
storing fuels in vehicles for more than 6 months. You should also take into
account the differences between summer and winter grades of petrol. Petrol
has a higher volatility in the winter in order to enable cold starting. For
this reason it is better to fill the tank with a winter grade fuel (16th
October - 14th April) rather than a summer grade.

Lubricants and Fuels Technical Services

540 Posts
1. Pump gas into gas cans.
2. Introduce water to gasoline. 1 part water for every 5 parts gasoline.
3. Agitate.
4. Siphon off the 4.5parts of pure gas.
5. Celebrate with a glass of 60 proof.

1 - 2 of 2 Posts