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Discussion Starter #1
Historically, I only use 93% premium unleaded fuel in the bike but had a friend say he switched to 100% gasoline and believed it made a difference in the engine performance. Was a little vague on exactly what was actually better and I was pressed for time so I didn’t get too far into the details. Curious if anyone here is using 100% gas and can see a performance improvement.
Thanks!
 

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I only use 91 Octane. I've got my choice of all-gas and gasohol. Can't see that all-gas vs gas + alky makes any difference. I know some folks don't like alky in the gas, I've had no real problem with it.

I remember a Harley rider tagging along on a trip and was complaining that he couldn't find 100% gas. I finally said, "you'll burn it all out by our next gas stop". Of course the snowflake had to run gasohol all weekend until we got home. I don't how much longer the Harley survived but he was on a Harley the next time I rode with his a couple of years later. Don't know if it was the same one or not. Maybe she blowed-up?
 

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I would, but 93 octane 100% gas not easy to find here, it’s usually regular or mid-grade.
 

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On the SS I use 92 octane pump gas, but my other bikes all get clear gas. There's a few gas stations near me that carry it, we keep 15 gallons in the garage to fill up with if we're not heading towards one of them on our way somewhere.

Ducati learned their lesson in recall costs with not preparing their bikes for blended gas in the 2000's. Everything they make now is blend-safe, save for the fuel level sensor apparently. Prior to that there all sots of issues with the plastics in the fuel stream degrading or plastic tanks swelling. They've switched back to metal wherever they could, and use safe plastic elsewhere.

The bikes that get clear gas are my track-only bike (a 2000's Ducati), my 1994 900SS, and my wife's 2014 Guzzi V7 Racer (because she insists on it). I also use it in the 2017 SS when I take it to the track, because all my gas cans are full of it already.

If you're having a hard time finding it, try https://www.pure-gas.org. They list all the stations that regularly carry clear gas, and have an app on Android and Apple that will map them out for you based on your location data.
 

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I try to run oxy free gas when I can because my bikes sit so much between riding and that’s when the ethanol comes into play. Ethanol attracts water so if your bikes sit for a week or two at a time between rides, finding non-oxy gas can be beneficial to how it runs and motor longevity.

As far as normal riding and performance, I personally have not seen, felt, heard it experienced anything different between the two as long as I ran it out. I have, however, experienced poor running with 10% ethanol fuel, without stabilizing it, after just 3 weeks of sitting. And other times after stabilizing the fuel and sitting 4 months.
 

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I think we only get 100%. Never ever seen ethanol published or advertised here. This whole E10 melarky had me quite confused when I originally got the SS then it was all nicely explained how other countries rip off their public by adding alcohol. Ahem.. gotta love the third world.
 

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Yeah, we gotta lot of feeder corn here, Amos. Even more so since the China embargo. They're always looking for markets for the stuff, chemicals, cattle & pig feed, corn oil substitutes, fuel, etc. So several states require that crap in the gas. As I said, I've never had a problem with it but it is what it is.

You can't eat it, that's what sweet corn is for.

Hopefully, we'll have legal hemp here which has more uses and is better for the environment. Of course, then there'd be competition.
 

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In France we have 98% octane and the 95 is blend with alcool, 10%. Some says that it's not really good for the engine but on the ducati manual they approve it.
Some uses 85% ethanol because it's cheaper but it need a engine preparation.
I only put 98% and when I'm in Switzerland I use the shell v power 100 but I didn't make a difference.
 

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I’m aware of the Pure-Gas link, hate to go too far out of my usual route to purchase. On my Airhead BMW, I only use pure gas as it doesn’t get used much.
 

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Gasoline Quality.

uk standard unleaded. is around 95 octane which I understand is the recommended minimum for the Supersport.I have already discovered that she runs smoother and crisper on Shell v power 99 octane.Its superb fuel if you can get it.
 

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Discussion Starter #12
All great perspective Agree, 100% is a bit difficult to find. 93 is typically the best I can find in my area (Knoxville, Tennessee) although I just moved here a month ago. When riding more in the coming spring and if I can find it, I may try it for a couple of tanks & see if I notice a material change in performance. Thanks all!
 

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I had a lawn mower that gave me fits until I started to run actual gasoline in it instead of the moonshine gas. Definitely made me think twice about the moonshine. I try to run gasoline whenever possible in the Ducati and in my Triumph. We seem to have quite a few options where I live because of the snowmachines. They don't like the moonshine either.

On a related sidenote. Octane (which is different than E85 or other moonshine blend numbers) is certainly misunderstood by so many. It is not a measure of quality. It is just that vehicles with high compression need a higher octane rating so that the fuel doesn't combust on its own during compression. It is just fuel that won't combust in a high compression engine until the spark fires off.

I see tons of people paying extra money for higher octane gas and putting it in a vehicle that is rated for 85 octane fuel. I believe they think they are purchasing "better" quality fuel. The Oil companies capitalize on this. High octane cost much more for the consumer and plenty of people are buying it. It is, however, appropriate for our bikes. Just match the owners manual :) which is what those car/truck people I am talking about should do.

I run 91 octane gasoline in My Precious. Occasionally on a road trip I have to put moonshine in it. No big deal I guess. :)
 

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First time I've lived somewhere where non-ethanol was even an option and it's at ever station; which is ironic because I'm in corn country. I've tried running 91 pure, 91 e10 and, lately, 88 e15 in my VW GTI. There seems to be no difference in mileage or power between them (maybe a little worse mileage with the e15). When I lived in VA I could easily find 93 and 91 wasn't an option; I got better average mileage, but I also did a lot more long distance driving, so that's probably where the difference lies.


I put whatever 91 I can find in my SS, or 93 when I sometimes find it. It has been a few months since I've ridden it thanks to winter, so I don't recall if I noticed a difference between 91 pure and 91 e10. Bike probably wouldn't like e15...
 

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First time I've lived somewhere where non-ethanol was even an option and it's at ever station; which is ironic because I'm in corn country. I've tried running 91 pure, 91 e10 and, lately, 88 e15 in my VW GTI. There seems to be no difference in mileage or power between them (maybe a little worse mileage with the e15). When I lived in VA I could easily find 93 and 91 wasn't an option; I got better average mileage, but I also did a lot more long distance driving, so that's probably where the difference lies.


I put whatever 91 I can find in my SS, or 93 when I sometimes find it. It has been a few months since I've ridden it thanks to winter, so I don't recall if I noticed a difference between 91 pure and 91 e10. Bike probably wouldn't like e15...
Cars are different than motorcycles. Modern cars have knock sensors that, when detecting knock (pre ignition detonation), will retard the ignition timing until the knock goes away. It's "safe" to use lower octane fuels in these vehicles, but expect reduced power, as you saw. Motorcycles do not have knock sensors, using a lower grade fuel than specified can cause pre-detonation which damages the piston and spark plug, and can ultimately destroy your motor.

Technically, lower octane fuel is easier to ignite and has a higher power density than fuels with higher octane numbers. However, with higher compression motors, there is more power density per CC of displacement than there is a reduction in power density in the fuel required to run them, so it's overall beneficial to use the correct fuel.

Most fuel manufacturers treat low octane fuel pretty poorly, as it's the cheapest for them to make and generally used on commodity quality engines. It doesn't make financial sense for them to supplement these fuels with cleaning agents and aromatics. Techron is the most famous of these additives, it's exceptionally rare to see 85 or 88 octane with Techron added, but their 89 and 92 fuels always feature it.
 
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Ethanol has a lower heat of combustion than the mixture of hydrocarbons in gasoline. If you use ethanol free gasoline you will get better mileage. Alkylate that @LowRyter doesn't like is the best fuel from many aspects. It is 100 paraffin. Paraffins are lighter, and have a higher heat of combustion than aromatics. They are also the best for reducing environmental issues and has less toxicity. There is a good reason why aviation fuel is primarily alkylate. Ethanol is not competitive with petroleum based fuels without our government subsidy. It is more expensive to produce than petroleum based gasoline.
 

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Ethanol has a lower heat of combustion than the mixture of hydrocarbons in gasoline. If you use ethanol free gasoline you will get better mileage. Alkylate that @[B]LowRyter doesn't like[/B] is the best fuel from many aspects. It is 100 paraffin. Paraffins are lighter, and have a higher heat of combustion than aromatics. They are also the best for reducing environmental issues and has less toxicity. There is a good reason why aviation fuel is primarily alkylate. Ethanol is not competitive with petroleum based fuels without our government subsidy. It is more expensive to produce than petroleum based gasoline.
Sorry but what I don't like? I saw the reference to me but not the subject. I've said that I've never had a problem with alky mix. And even said that I rode with a "snowflake" that complained about it. I didn't mention but some folks have problem with corrosive nature and the tendency to absorb water but again, I haven't had a problem.

I've had problems with water in my lawnmower gas. But I leave that can 3/4 empty outside. So I know it draws water just from humidity.

? ???
 

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I run mostly pure gas in mine at 90 octane. No issues with it so far. Any time it's not going to be ridden for a while, I top it up with pure gas. The station that sells it is about 30 miles from me, and I always have some in a gas can for my lawn equipment to top up from. I've heard Shell mid grade is ethanol free, but not found any info to back that up. Best bet is if you have to use gas with ethanol in it, always run stabilizer in it as well.
 
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