petrol

[grant71]

Hello everybody. Happy Easter.  i have noticed numerous complaints by bikers re petrol quality. it seems especially in the US that petrol is of bad quality or contaminated. Here in South Africa, i have never had a bad experience in that regard.  i use mainly Caltex which is produced with the techron additive. a while ago i had to replace the fuel sensor on my K100. the tank was clean as a whistle. can anyboy give a reason for this bad fuel.

[Zipster]

We have Asda stores in the UK which are part of the Walmart group and they have petrol stations linked to their stores. Asda fuel gets less MPG than other fuels and this has been attributed to a detergent additive that Asda add which is claimed to be better for the environment. In effect they are diluting the fuel so when you pay for 1 litre of fuel, you're actually getting less than a litre and a big dose of detergent. In answer to your question, bad fuel is the result of diluting it in order to increase the profit margin further up the retail chain.

[grant71]

thats very interesting thanks. quite a long time ago a major supermarket group Pick 'n Pay tried to get involved in petrol retailing here in SA. the  govt at the time nailed them and they stopped the campaign. i suppose for the same reasons viz. profit. i remember when i lived in London 61 the price of Golden was 5 shillings a gallon. high octane stuff of course. for a few months i worked in Shepherds Bush as a petrol jockey. In those days the police whatever special squad drove fast cars called Dart. But the strange thing was they used to fill up with lower octane petrol. of course the Dart engine never performed as it should

[jacksdad1963]

The major problem we face is the use of ethanol in fuel, its currently 5% here, but will soon be increased to 10%.
The problem for many of us is that older machines don't like it! I restore classic motorbikes and have to line the fuel tanks and replace all rubber fuel pipes because ethanol destroys them! If left for more than a few weeks the fuel goes bad, and releases water which rots untreated steel...and ethanol dissolves the carb jets and other internal parts.
You must use fuel additives to combat this in any carb engines: fuel injection motors don't suffer as the hoses are more modern construction, but the fuel will still 'go off' if left for a while, something that will affect machines that arent used frequently, this also applies to lawn mowers, strimmers etc.
Basically, modern 'eco friendly' fuel is rubbish, yet costs us more!

[Elipten]

Here in USA the government is making 10% alcohol be added to gas.  It suck big time.

[jacksdad1963]

Thats whats happening here, ethanol is supposed to be the big cure-all but its not! Millions of acres of land will be used to 'grow fuel' and farmers are getting subsidies for this, plus the land isn't being used to grow food any more!

[TaosBrick]

In Taos, New Mexico US we've the good fortune to have ONE Phillips 66 station that dispenses 90 octane ethanol-free for about $4.10/gal. My '73 R75/5 drinks there regularly. When traveling on my '92 K75, I try and stop at Chevron exclusively, however they pretty much don't exist in the eastern US. I go for Shell when back there.
  I'd say about 98% of petrol sold in the US has 10% ethanol. Bleah. :musicboohoo:

[drut]

Here in UK current ethanol level is 5% but EU is pushing for 10%,aside from the mileage reduction the effect of this on some older fuel system components could be "interesting".

http://www.telegraph.co.uk/motoring/classiccars/9108430/The-ethanol-threat-to-classic-cars-and-bikes.html

http://news.sky.com/story/1207390/new-e10-petrol-reduces-fuel-efficiency

[tg4360]

When I first got my bike, the pump was locked up.

The pump holder was turning to goo and there was about two inches of what looked like sterno jelly like stuff in the bottom of the tank.

That goop along with the water sucked up by the alcohol had started to corrode the bottom of the tank.  I was lucky because I went from VA to Key West and back with nothing but several paint bubbles holding fuel in the tank.

I've replaced all the rubber bits inside with alcohol resistant stuff and lined the bottom of the tank.

I also have a BSA B25 that has a fiberglass tank.  It has sat for a few years not being run and when I got it out, the throttle slide started sticking.  It was the gas melting the tank from the inside out glueing the slide to the carb.

I had to line that tank also.

All this and LESS gas mileage too.  How fun.

[TimTyler]

I watch my highway mileage on long trips and have found that ethanol and non-ethanol fuels don't make a difference. Speed makes a difference and my mileage drops when the speed limit goes up.  :dunno

If I think the bike might be parked and unused for a while I will fill up the tank with ethanol-free fuel at a local pump.

I don't agree with the politics of ethanol additives though. I'd rather pay more for fuel and have farms grow people food, organically when possible.

[TaosBrick]

I don't agree with the politics of ethanol additives though. I'd rather pay more for fuel and have farms grow people food, organically when possible.

Amen to that !

[ttown95LT]

Actually the real problem with American petrol is; our ethanol we add comes from corn not sugar cane.  If a Brazilian were to chime in they would let you know they have no issues with ethanol and older vehicles and most stations down there sell petrol with 15% ethanol, the difference theirs is made from sugar cane.  Ethanol manufactured from sugar cane creates almost twice as many BTU's than ethanol from corn.  Thank the agriculture lobbyists for that.  The part I don't understand is the last time I was in the Houston area many of the sugar plantations and mills have shut down, and nothing is being grown on those plantations, cause the government is actually paying them to idle their land. :dunno2:

[TaosBrick]

Ok, I'll buy it that sugar cane ethanol might have more jooce than that produced from corn. But - is it any LESS hygroscopic? And what about eating up older rubber and plastic fuel system components? I would find it hard to believe that sugar jooce is any less deleterious in those two regards.

[wmax351]

Ethanol is ethanol is ethanol. Doesn't matter if it comes from corn, sugar cane, milk (http://newsfeed.time.com/2013/04/12/british-dairy-farmer-creates-pure-milk-vodka/), or cellulose. It's chemically identical. Sugar cane should produce more BTU's per acre, but it requires more sun.


Ethanol, with proper fuel system components, is actually a pretty good fuel. It has a very high knock resistance, burns very clean, and is quite cheap to make. One off the promising options for future fuels is Cellulosic ethanol, which is made from cellulose of plant stalks, rather than the sugar from corn or sugarcane. The hold up has been the difficulty genetically engineering yeast or bacteria to digest the cellulose properly, but once that happens, ethanol can be made from basically any biomass: Think Straw, bamboo, paper pulp, sawdust, etc.

[TaosBrick]

Yep. Trust Max to have a scholarly take. But what about ethanol's ability to soak up water like a spnge? Regardless of what your fuel system components are made of, water in your petrol just ain't good for things like cylinder liners, valves and exhaust systems, unless these things are made of fancy alloys. Older whips just don't like that ch!t. And one has to do a lot of retrofitting to make older carbs and other bits tolerate it too.

[wmax351]

Ethanol will absorb water, and the concern with gasahol is that when it absorbs water past a certain point, the water/ethanol mix (which are miscible http://en.wikipedia.org/wiki/Miscibility) crashes out of the ethanol/gasoline solution, which can cause corrosion. With pure ethanol, or e85, there is less of an issue because the critical concentration of water is a much higher proportion of the total solution.


The actual water in the fuel system isn't a big deal, at least when the engine is hot. In some cases of high performance engines (usually forced induction; turbo- or super- charged) water (sometimes mixed with ethanol) is injected into the engines to increase the charge density and cool the charge to prevent engine knock. [size=78%]http://en.wikipedia.org/wiki/Water_injection_(engines)[/size] Introduction of water into engines is one method for de-coking a cylinder head. The only concern is a significant amount of moisture remaining in the engine once cooled.

[TaosBrick]

Ah, so steam is not necessarily corrosive? Guessing not, as engines made with far less advanced metallurgy ran on it for over a century.