Why I don't think fuel stabilizer on an EFI bike is necessary

S

Sunspark

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Mechanical:
-Fuel doesn't sit in bowls evaporating away like it does with carbs.
-EFI agitates the fuel to a certain extent

Chemical:
-Fuel stabilizers as I understand it try to spread a thin layer of oil on top of the gas in order to act as a barrier to oxidation and make it last longer as a result except:
a) the tank is not an open air container, even if it is vented it is cold outside so it won't need to be venting.
b) chemical reactions during cold are significantly slower than when it is hot.
c) pure gas just doesn't go bad that fast. In a sealed container it can last a year.
d) If you're using 91 it won't have more than half a litre of ethanol in it which has some fuel stabilization properties of its own (water absorption).
e) As fuel ages it loses some octane. My bike is specced for 87. I use 91 in part due to the ethanol free-ish thing. If anything, it is approaching closer to spec.

It is ridiculous the idea that a little plastic bottle is somehow needed that will change the chemistry of the hydrocarbon chain and somehow make it better than ever. Something that the refineries cannot do.

Is it bad to use a stabilizer to make that barrier against oxidation? No. Do you need to? In my opinion, no unless you planned to store it 6 months.
 
Yeah OK. We'll see your post asking where to get your injectors cleaned or why your bike runs like crap next season.

From my fingertips using Tapatalk.
 
toybm said:
Yeah OK. We'll see your post asking where to get your injectors cleaned or why your bike runs like crap next season.

From my fingertips using Tapatalk.
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+1

It is all about preventative maintenance. A $5 bottle will last you at least 2 years.
 
How is a vented tank a sealed container and how does ethanol absorbing water stabilize your fuel?
 
For the amount of money you spend on 91 octane instead of the recommended 87, you could afford to buy a bottle of fuel stabilizer.
 
Ive left bike without fuel stabilizer for over 12 months and had it start first go when I got back with no issues at all. Mind you thats in Aus where temps stay nice all year around. My bike in storage there now is sitting for over 3 years, Ill let ya know how it goes when I get back there and start her up.
 
Ethanol is one of the worst things in fuel for storage. That's why manufacturers are recommending that blue Startron stuff now instead of StaBil. Or just use Shell 91 before storing.
 
Sunspark said:
Mechanical:
-Fuel doesn't sit in bowls evaporating away like it does with carbs.
-EFI agitates the fuel to a certain extent

Chemical:
-Fuel stabilizers as I understand it try to spread a thin layer of oil on top of the gas in order to act as a barrier to oxidation and make it last longer as a result except:
a) the tank is not an open air container, even if it is vented it is cold outside so it won't need to be venting.
b) chemical reactions during cold are significantly slower than when it is hot.
c) pure gas just doesn't go bad that fast. In a sealed container it can last a year.
d) If you're using 91 it won't have more than half a litre of ethanol in it which has some fuel stabilization properties of its own (water absorption).
e) As fuel ages it loses some octane. My bike is specced for 87. I use 91 in part due to the ethanol free-ish thing. If anything, it is approaching closer to spec.

It is ridiculous the idea that a little plastic bottle is somehow needed that will change the chemistry of the hydrocarbon chain and somehow make it better than ever. Something that the refineries cannot do.

Is it bad to use a stabilizer to make that barrier against oxidation? No. Do you need to? In my opinion, no unless you planned to store it 6 months.
Click to expand...

Is your post based in fact or is it your personal opinion? I disagree with several of your points.

Over time, untreated "pure gas" will (a) lose it's volatility due to evaporation, (b) oxidate and (c) accumulate moisture. Fuel stabilizer helps to slow this process. Oxidation of gas causes gum or varnish to build up. Accumulation of moisture can lead to corrosion in your tank and fuel lines. Both of these will easily clog up your fuel injectors which have even smaller ports than a carburetor's jets.

The general rule of thumb is gas will start to go "bad" after 2-3 months. With fuel stabilizer, it can stay "good" longer (possibly up to a year).

Ethanol (an alcohol) is hygroscopic (absorbs water) and increases the corrosivity of gasoline. It is added to gas to make it burn more completely but it does so with a lower BTU (not octane). This means that the more Ethanol that's in your gas, the lower your fuel economy will be. Ethanol does not act as a fuel stabilizer because it absorbs more water into your gas. This doesn't remove water from the gas (think: it's all in your gas tank). Ethanol also has a higher octane rating than gasoline.

In Canada, our Ethanol content is 5-10%. The octane rating of the gas you buy doesn't change the percentage of Ethanol that is in it. Other additives are used to modify the octane rating. All engines produced now are rated for at least an E10 fuel (10% Ethanol). Flexfuel engines can operate on E85. Buying 91 octane gas doesn't minimize the amount of Ethanol in your fuel.

To say that gas loses octane is not correct. It loses it's volatility due to evaporation and absorption of water. Buying 91 octane gas won't help in this situation because the Ethanol content is the same.

The only reason to buy a higher octane fuel is if your engine is experiencing pre-detonation or knock. If your bike (or car) runs with 87 octane and doesn't knock (which it shouldn't) then using a higher octane fuel pointless. It's just costing you more money than you should be spending.
 
dricked said:
How is a vented tank a sealed container and how does ethanol absorbing water stabilize your fuel?
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I think of it as akin to a pressure valve on a steam espresso coffee maker like a Moka. If pressure builds then the flap/springs open and releases it. I suspect this valve works in both directions as it helps prevent tank crush from a vacuum as shown by people who have had their tanks sucked in by using valveless caps or a malfunctioning cap. So, when the bike is off, the pump is off and there is not much of a pressure fluctuation in a cold storage environment. If it was completely open then you would easily be able to smell the gasoline evaporating. But since you don't then therefore there must be a certain amount of seal.

Ethanol can stabilize but not in the way you think. Yes, it can destroy everything in sight on older bikes that have hoses/seals etc that dissolve in alcohol and can reduce your power efficiency when operating, however, I you mix water and gas, water will be on the bottom and gas on top as the density is different. The fuel pump is on the bottom. So if you have a lot of water condensate or whatever, it'll be at the bottom and when you start it the engine is going to try and run off water first. So, if the ethanol can absorb some water into itself it'll form another compound still suspended in solute form in the fuel that can then be burnt out in small amounts at a time.
 
Agreed on MOST points except the OP stated he is buying SHELL 91 which is marketed as "ethanol free" so in that case the octane does change the level of ethanol. Other than that you are 100% correct in the other points.

My dealer actually told me NOT to run 91 in he engine as it is not designed to operate at 91 it is optimized to operate at 87 octane.

Of course the main issue with the OPs "theory" is stating that the gas tank is a "sealed container" given that "it is not venting in the cold" It has an open vent line and therefore by definition it is not a "sealed container"

Given this is my first FI bike I called the dealer service manager on recommended "winterization" and they recommend stabilizer. My bike went to sleep mid Nov and won't likely see the light of day again until Mid May or so. ( I perfer to wait till all the salt and sand has cleared away living in the rural setting this is generally later than the urban areas.

mroberto said:
Is your post based in fact or is it your personal opinion? I disagree with several of your points.

Over time, untreated "pure gas" will (a) lose it's volatility due to evaporation, (b) oxidate and (c) accumulate moisture. Fuel stabilizer helps to slow this process. Oxidation of gas causes gum or varnish to build up. Accumulation of moisture can lead to corrosion in your tank and fuel lines. Both of these will easily clog up your fuel injectors which have even smaller ports than a carburetor's jets.

The general rule of thumb is gas will start to go "bad" after 2-3 months. With fuel stabilizer, it can stay "good" longer (possibly up to a year).

Ethanol (an alcohol) is hygroscopic (absorbs water) and increases the corrosivity of gasoline. It is added to gas to make it burn more completely but it does so with a lower BTU (not octane). This means that the more Ethanol that's in your gas, the lower your fuel economy will be. Ethanol does not act as a fuel stabilizer because it absorbs more water into your gas. This doesn't remove water from the gas (think: it's all in your gas tank). Ethanol also has a higher octane rating than gasoline.

In Canada, our Ethanol content is 5-10%. The octane rating of the gas you buy doesn't change the percentage of Ethanol that is in it. Other additives are used to modify the octane rating. All engines produced now are rated for at least an E10 fuel (10% Ethanol). Flexfuel engines can operate on E85. Buying 91 octane gas doesn't minimize the amount of Ethanol in your fuel.

To say that gas loses octane is not correct. It loses it's volatility due to evaporation and absorption of water. Buying 91 octane gas won't help in this situation because the Ethanol content is the same.

The only reason to buy a higher octane fuel is if your engine is experiencing pre-detonation or knock. If your bike (or car) runs with 87 octane and doesn't knock (which it shouldn't) then using a higher octane fuel pointless. It's just costing you more money than you should be spending.
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I'll write more later but I will say quickly that even with Shell 91 you will get all the 87 that was in the hose from the person ahead of you. That will have up to 10% ethanol. The company claims it is only half a litre of 87 in the hose. I don't believe them. In any case, that's still a minimum of 50 mL of pure ethanol in your tank. I like to think of it as the same as having bought a bottle of stuff.
 
This is true. If you want "ethanol free" (91 shell) it's best to bring a jerry can for the first litre and then the rest to the tank. The reason being is that 1 hose share all the grades offered in a pump. Thus depending where and how far that meter is from the nozzle, youre essentially getting the previous clients gas thats left from the meter to the nozzle.

It's up to a liter but it varies per company and how far the meter is from the pump
Sunspark said:
I'll write more later but I will say quickly that even with Shell 91 you will get all the 87 that was in the hose from the person ahead of you. That will have up to 10% ethanol. The company claims it is only half a litre of 87 in the hose. I don't believe them. In any case, that's still a minimum of 50 mL of pure ethanol in your tank. I like to think of it as the same as having bought a bottle of stuff.
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I agree to some extent but not all points. Ive been putting the fuel stabilizer in my bikes for a few years now and what I notice in the spring is my bikes run like crap first tank of fuel. Stabilizer or not. I even had a 3 month old tank of fuel (stabilized) in my GPz 750 go so bad it wouldn't allow the bike to start. Once draining the tank and replacing with brand new fuel, the bike fired right up and ran well. Now I am in the habit of running my tanks almost empty near the end of the season, draining all remaining fuel and storing the tank indoors with a coat of WD40 on the inside. I then rinse the tank with fuel before filling it in the spring. All my bikes are carbed bikes so I drain the bowls and run the engine till she takes all fuel from the carbs. this seems to help a great deal in carb cleanliness in the spring. Though you are talking about fuel injection but those injectors are pricey and do get gummed up, even on stabilizer. Believe it or not.
 
hedo2002 said:
Agreed on MOST points except the OP stated he is buying SHELL 91 which is marketed as "ethanol free" so in that case the octane does change the level of ethanol. Other than that you are 100% correct in the other points.

My dealer actually told me NOT to run 91 in he engine as it is not designed to operate at 91 it is optimized to operate at 87 octane.
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I didn't know that Shell's V-Power 91 octane didn't contain Ethanol. I assume their lower-octane fuels do.

An engine that is designed to run on 87 octane cannot be damaged in any way when operated with a higher octane fuel. It is, however, a waste of money to use a higher octane than is needed.


1978550 said:
I agree to some extent but not all points. Ive been putting the fuel stabilizer in my bikes for a few years now and what I notice in the spring is my bikes run like crap first tank of fuel. Stabilizer or not.
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Did you see Sunsparks post about water sitting on the bottom of the tank? When you added stabilizer to your gas, how old was the gas? Stabilizer won't fix "bad" gas. If there's already a large moisture content in your gas, then stabilizer won't do anything there. I wonder if it already had an accumulation of water when you stored the bike. Otherwise, I'm not sure why 3 month old gas wouldn't run in your bike (assuming the gas was relatively new when you pumped it into your tank).
 
mroberto said:
Did you see Sunsparks post about water sitting on the bottom of the tank? When you added stabilizer to your gas, how old was the gas? Stabilizer won't fix "bad" gas. If there's already a large moisture content in your gas, then stabilizer won't do anything there. I wonder if it already had an accumulation of water when you stored the bike. Otherwise, I'm not sure why 3 month old gas wouldn't run in your bike (assuming the gas was relatively new when you pumped it into your tank).
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The Gas that was in the GPz was only a couple months old at most. I was shocked myself that the gas had gone bad that quickly. An auto shop teacher friend was actually the one to catch that the gas had gone bad. While looking at the bike, he was able to smell the gas and notice it smelled 'off'. I didn't believe him but That's when I decided to drain the tank and put in fresh gas. Lo and behold, the bike started first button push. I would have never believed it myself, but I seen it with my own eyes. Now, maybe that was a special case as I am unsure of where that fuel came from, but it happened. From that experience, I noticed every spring my 2000 GS500e would run a bit rough in the spring. for 3 years now I have been draining that tank at the end of each season and filling up with brand new fuel in the spring. I Have not yet seen the same spring time issues as when I was using stabilized fuel. Or non stabilized fuel for that matter. But this is only my experience.
 
Honestly with a fairly new, modern bike, I doubt any of this matters much if the bike is only going to sit for 2-4 months at most. Leave it for a year or two, then maybe.

With that said, Sta-bil and the likes are cheap considering how little is needed each year, so I consider it cheap insurance. I'd rather think I wasted $2 on stuff I dumped in my tank than wonder if the bike will start in spring.
 
skapan said:
Ethanol is one of the worst things in fuel for storage. That's why manufacturers are recommending that blue Startron stuff now instead of StaBil. Or just use Shell 91 before storing.
Click to expand...

PSA: Most Canadian Tire gas bars also have ethanol-free 91.
 
I've also found bikes to run like crap on fuel that was in the tank over the winter, regardless of Sta-bil or not.

Since then, I store them with the fuel tank as empty as possible, in a temperature-controlled area. While the fuel tank is "vented", on modern bikes that is done through a pressure/vacuum relief valve. As long as the temperature remains consistent (doesn't have to be exact), this valve remains closed, and that means moist air can't get in and cause condensation and rust. I always make the last fill-up before winter with Shell V-power due to no ethanol.
 
Recent formulations of StaBil accomodate for the ethanol in the fuel. Gasoline varnish and the loss of the more volatile fractions of the gas are good reasons to use stabilizer even on fuel-injected bikes. Also, I could be wrong but most fuel injection systems on motorcycles are returnless, no? So the only way for any gum/varnish to exit the fuel system would be through the injectors.
 
My 2007 Kawasaki Vulcan 1500 FI owners manual states: remove fuel from the tank with siphon or pump then run the engine on idle until the all the fuel is burned off, then remove the fuel tank and store it well. (if left for a long time the fuel will break down and clog the fuel system).... Really, remove the tank??? I just top up the tank with premium, change the oil, wash the beast and stuff rags in the tail pipes.... starts fine in the spring without Stabil etc. or removing the tank .
 
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