Does High Octane Fuel Store Longer?

Y'all sure know how to party! LOL

My carborated bike, an 09 Honda Shadow, sat for a number of years before I bought it.

The previous owner used Seafoam to get it started before he sold it to me, but it needed to be choked to start, even in warm weather.

It ran fine all summer and through the winter too, then one day the following spring it decided it didn't want to start.

I only rode it once a week during that first winter, and I put a healthy amount of Stabil in the tank to try an keep the gas from going stale.

The following Spring, she was idling a little rough, so on the advice of a Honda motorcycle forum, I gave it good dose of Seafoam... And that seemed to fix it.

She ran better than ever for the first month after the Seafoam.

One day as I was letting it warm up, getting ready to take the choke off, it just died.

The Honda shop removed and cleaned the single carb shared by both cylinders. They charged me for 90 minutes labor, which I thought was very reasonable... But I would prefer not to hire them again!

Last winter I basically did the same things that I had done the previous winter, Stabil 1st and Seafoam after, and had no problems come Spring.

I don't think I've had to use the choke since April... But now we've had a couple of 50F degree nights and she's needing the choke again in the morning.

Which is what got me thinking so I started this thread...

Even here on BITOG, there seems to be a variety of opinions... Apparently everyone has one!

Thanks for all your replies and goodwill... Rubber side down!
 
Y'all sure know how to party! LOL

My carborated bike, an 09 Honda Shadow, sat for a number of years before I bought it.

The previous owner used Seafoam to get it started before he sold it to me, but it needed to be choked to start, even in warm weather.

It ran fine all summer and through the winter too, then one day the following spring it decided it didn't want to start.

I only rode it once a week during that first winter, and I put a healthy amount of Stabil in the tank to try an keep the gas from going stale.

The following Spring, she was idling a little rough, so on the advice of a Honda motorcycle forum, I gave it good dose of Seafoam... And that seemed to fix it.

She ran better than ever for the first month after the Seafoam.

One day as I was letting it warm up, getting ready to take the choke off, it just died.

The Honda shop removed and cleaned the single carb shared by both cylinders. They charged me for 90 minutes labor, which I thought was very reasonable... But I would prefer not to hire them again!

Last winter I basically did the same things that I had done the previous winter, Stabil 1st and Seafoam after, and had no problems come Spring.

I don't think I've had to use the choke since April... But now we've had a couple of 50F degree nights and she's needing the choke again in the morning.

Which is what got me thinking so I started this thread...

Even here on BITOG, there seems to be a variety of opinions... Apparently everyone has one!

Thanks for all your replies and goodwill... Rubber side down!
It is common to need to use the choke on a carb bike. That's why they put them on there.
My Suzuki 500 needed the choke even in the summer to get it started.
 
Rear carb from my TR6 after ~7 years of driving maybe 1k/yr and 6 mos of off season storage cycles. Ethanol in fuel probably has no adverse effects on modern engines or those driven frequently, but not ideal for this vehicle and usage profile:
f carb deposit 17.jpg

Same carb after I started religiously using Sta Bil 360 Marine, but with only 5 or so years in similar service;
rcarb22.jpg
 
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Ethanol is not the problem with gummed up carburetors. It was happening for decades and decades and decades before ethanol was ever introduced. In fact, it started as soon as carburetors were created.
 
Ethanol is not the problem with gummed up carburetors. It was happening for decades and decades and decades before ethanol was ever introduced. In fact, it started as soon as carburetors were created.

Ethanol evaporates with no residue, which is why it's a good cleaning solvent (denatured alcohol is mostly ethanol, with a little bit of methanol added to make it undrinkable).

Gasoline, on the other hand...does leave a residue. And a stink. Whether it's E0 or E10.
 
As the riding season is winding down for much of the Northern Hemisphere, I am looking for ways to keep my carborated Honda Shadow from needing a full carb clean next Spring.

E0 is not available anywhere near where I live. In the past I have used Stabil gas treatment and Seafoam, and I try and ride a mile or two every week or so, even if it's cold outside.

Last year I filled up with high octane at the beginning of Winter, with the idea that the gas might lose octane after sitting for a while, but I have no empirical evidence that this would be true.

Anyhow, I figure that BITOG is a good place to look for empirical evidence, or at least anecdotal evidence...

Thanks in advance!
No
 
Gasoline doesn't lose its octane rating sitting in the tank for the type of situation being discussed. As well, if you're going to ride one or two miles a week don't ride it at all. If you're not going to fully warm it up you're not going to do it any benefit. More harm than good. Drain the float bowls, top the tank off, add stabil and put it on a battery tender.
 
Gasoline doesn't lose its octane rating sitting in the tank for the type of situation being discussed. As well, if you're going to ride one or two miles a week don't ride it at all. If you're not going to fully warm it up you're not going to do it any benefit. More harm than good. Drain the float bowls, top the tank off, add stabil and put it on a battery tender.
My little "ride around the neighborhood" is actually ten to twelve miles, depending on which route I take.

But yeah, straight Stabil is what I am going to use this year. Thanks for the reply!
 
I've been storing cars, motorcycles, lawn mowers, power washers, etc over the last 20+ years with E10 in the fuel system and have never had an issue. Many of those years were with no fuel stabilizer either. They all fire up 5-6 months later and run great, just like they were just used.
Ive had complete opposite effect, after about 3 to 4 months with no stabilzer the fuel discolors bad and the motors run flaky. Thats all of them the lawnmower, the weed eater and the Blower.

Southern Texas , I have to run fuel stablizers in those, if I want the fuel to go more than 90 days
 
Ive had complete opposite effect, after about 3 to 4 months with no stabilzer the fuel discolors bad and the motors run flaky. Thats all of them the lawnmower, the weed eater and the Blower.

Southern Texas , I have to run fuel stablizers in those, if I want the fuel to go more than 90 days
What brand of gasoline are you using? I've never had an issue in over 30+ years with Chevron.
 
I've exclusively used zero ethanol fuel in everything with a carburetor(s) for the past 15 years. Also, for my home gasoline storage. I dose the tanks with Stabil 360 (used to be marine formula) for winter storage. The original Stabil would be fine for me not using ethanol, but that doesn't seem to be available anymore. All those rubber o-rings in a stored 4-carburetor motorcycle would a real party for ethanol.

Sadly, most all motorcycle petcocks have been vacuum operated for decades so you can't just run the carburetors dry. Unless you have one with a position feature that allows actual shutoff. An old BMW boxer bike I had for many years had glorious twin Karcoma manual petcocks. The carbs were extremely easy to access on each side as well. I can't remember how many times I took off down the road on that Beemer and realized a half mile later that I hadn't turned the petcocks on.
 
Gasoline blenders alcohol concentrations vary by grade of gasoline, You will get the least with premium.

Fill the tank with premium, add some Techron.
 
"Ethanol blends are politically driven garbage" Oh Sooooooo True !

I find it hard to call it garbage simply due to a shorter shelf life. At just 10% concentration, the difference in fuel economy isn't all that much. It's an easy way to boost octane without making the fuel unresponsive or increasing the cost, it increases the fuel's heat of vaporization which aids in power and reducing cylinder temperature, and helps reduce the distillation curve in the mid range which aids in fuel vaporization and air/fuel homogenization.

Also, gasohol was around a looooooong time before the EPA began salivating over it. Gas stations across the midwest were selling it back in the 1930s.

Gasoline blenders alcohol concentrations vary by grade of gasoline, You will get the least with premium.

Fill the tank with premium, add some Techron.

I measure ethanol content at the pump pretty regularly. I haven't seen that at the pumps where premium contains ethanol. Premium has either contained no ethanol or is the same content as the regular from the same station. The last batch of GEM fuel I blended last week, I tested the premium against the regular I bought for the lawn equipment and both were right at 10%.
 
No. Octane rating only affects the resistance to pre-ignition. Having said that there are multiple ways to affect the octane rating of gasoline so it can be more complicated, but in general the stability of the gasoline mixture has nothing to do with the octane rating in and of itself.

For years I have been reading many articles including this one, that say the higher the octane fuel, the more stable it is, therefore in storage it lasts longer per se. You’re saying that’s not true?

 
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