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Has anyone had starting problems with rarely used bikes (like once a month) since the ethanol addition? Because I have 4 bikes they don't get used a lot, and they have become harder and harder to start because it seems the idle circuits in the concentrics get gummed up so easily, or else the volatile fractions are being lost.. On my BSA I have a choke which is the only reason it starts easily. My commando used to start by flooding the carbs, but now it doesn't and I am in the process of adding chokes. Funny thing is, once it warms up it will idle at 800RPM.
The Trident I have been working on started easily after a rebuild, but then because of my big bore kit problems it was a month before it was ready to go again, and it won't start (no chokes). The plugs aren't wet or even smell of gas. It seems that even after extensive poking, pressure cleaning, compressed air etc there is no fuel getting to the engine. My 2002c Bonneville with Kehin carbs doesn't seem to have the same problem, but it does need full choke here in Florida.I use fuel stabiliser in all my bikes. I have heard stories about gas gelling etc. but this seems farfetched to me. I'd be interested to hear of any similar experiences.
 

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I was taught , and still do switch of the fuel tap about 2-300 yards or so before finishing my journey if intending to leave the bike for a week or more.. ( for me even overnight). The reason is the more volatile ( read easier to vaporise) components diappear first, leaving the heavier less likely to vaporise part behind. If the fuel does not vaporise it wil run desperately weak if at all and will make starting difficult. More modern carbs are supposed to not allow the fuel in the foat bowl to vaporise, so they stay fresh longer. Flooding sort of flushes the fuel in the float bowl.
I suspect the alchohol disappears first leaving you with a thicker incalcitrent mixture.
 

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I only use 'top grade' fuels. The only ones available in my area are Chevron /Texaco and Shell. I also only buy the high octane 'flavor'. I do add a TetraEthylLead additive to my fuel so that I'm running a leaded fuel closer to the octane rating the bike was built for. I have heard really good things about the 'Techron' additive fighting the ill effects of ethanol. I add a bottle periodically to my van and a couple of ounces to the bike every other or every third tank. When I'm parking the bike for more than several days, I turn off the petcock and run the carb dry.

The fact is that modern E10 fuel just plain sucks and it's only the select few of us who care. Unfortunately, we're stuck with frequent carb rebuilds and fuel-related headaches.
 

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I feel gas with ethanol does not have the shelf life and goes bad faster. I like to buy my gas at a busy gas station where i know there tanks don't have stale gas in them. I have friends that live in smaller towns that don't sell the volume of gas that city gas stations do and they seem to have more problems with there small engines.
 

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The reason gasoline that contains ethanol goes bad faster is due the fact that the alcohol absorbs moisture. Especially if you store your gas in one of those red plastic cans, the alcohol can absorb moisture through the plastic. I store Methanol because I mix my own fuel for my model airplanes, and have run into storage problems in the past. It is best to store fuels containing alcohol in a metal container set above ground or on a piece of wood, not on the concrete. So, if you have a float bowl full of gas, the carb is the perfect place for contact with air :) and the gas in the bowl will go bad, making it very difficult to start, since the fuel has much less energy and requires a richer mixture to fire.
 

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All of the above is as we are taught here in Australia.Can you blokes still buy fuel without ethanol in it at the pump. We dont mind using ethanol blend in the old jetted accordingly. But if its a vehicle that sits for any period of time forget about it.
 

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Discussion Starter #7
All of the above is as we are taught here in Australia.Can you blokes still buy fuel without ethanol in it at the pump. We dont mind using ethanol blend in the old jetted accordingly. But if its a vehicle that sits for any period of time forget about it.
Problem is we don't know just how much ethanol is in the various mfrs as the pumps all say "contains UP TO 10% ethanol, so it could be 5% in Shell, 10% in Chevron, we don't know.
 

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I have a problem with my old 1968 Lambretta having to do with leaving the bike for a month or more then going to start it, won't start. This is even though I had the engine rebuilt a year ago with new seals, rings, etc, and the carb rebuilt as well. Well, I started noticing that the gas line is full of gas with the gas valve shut off of course when I leave it, and when I come back a month later the gas line is empty (and I can't start it). I talked to my mechanic and here's what he said.

There is most likely a slight leak past where the float needle rests on the float in the carb. The gas in the float above a certain level, as well as the gas in the gas line probably slowly leaks past the needle/float interface and goes into the motor, flooding it. Also the ethanol in the gas is prone to evaporation leaving behind a gummy residue.

What I intend to do in the future. Turn off gas valve, run it at idle until it stalls. Then there won't be any gas left in carb or gas line to cause these issues. I would recommend with anyone if you're leaving your bike for more than a month and have ethanol laced gas, run the bike with gas valve closed at an idle until it stalls. I was a little concerned with my Lammy since it's a 2 stroke with oil/gas mixture that the bike's bottom end wouldn't be getting enough lubricant as it runs out of gas but was told that at idle it doesn't really matter. That's not an issue with the Triumphs anyway, since they're 4 strokes.
 
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