Fuel Recommendation by Google AI

What fuel do you choose for your XS650?


  • Total voters
    19
  • Poll closed .
A Quick Trip near me sells 91 E0.
Goes in my bike, mower, chain saw.... anything with a carb gets E0
In Norway and Sweden, many of us use a synthetic(?) gasoline for those tiny engines (Alkylate gas?) A common brand is "Aspen", and comes in several flavors, from chainsaw premix to race fuel. I use Aspen premixed in my Stihl chainsaw and weedeater. Keeps "forever", unlike E10.
 
In Norway and Sweden, many of us use a synthetic(?) gasoline for those tiny engines (Alkylate gas?) A common brand is "Aspen", and comes in several flavors, from chainsaw premix to race fuel. I use Aspen premixed in my Stihl chainsaw and weedeater. Keeps "forever", unlike E10.
I’ve never heard of such a thing, although we can buy premixed 2 stroke fuel in a can at hardware stores. It’s probably similar.
 
Did a search through my internet browser, has an AI search feature that sometimes posts a full answer, (other times I have to click on it to get the answer), with where it referenced it info from.

Top of the page browser source to the question Is your post today and the AI search is from 2 sources, one being XS650.com

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And I use 91ron standard fuel.
 
I have to say in cases like this, AI doesn't know shit. The nuances are just too complex for it to decipher.
AI is just trawling the net, albeit faster than you or I could, and presumaby summarising what it finds on loads and loads of What's the best fuel? threads. So I doubt AI would uncover any great new insights if you asked What's the best oil for my XYZ?
 
I Also use as high octane I can find on XS 650
But In February I Bought a 1987 Volvo 744 the motor B 230 F

The factory Recommends 95 Octane ( dont know what its called in the US )
The reason is that the Ethanol or whatever they mix In Helps clean the Injectors and Valves better.
I was surprised reading it . In the specifications there was other motors same year with higher Octane
Recommendations .

To now and then pour 95 in the bike is perhaps not entirely bad . But avoiding hot situations
Dirty pilot Jets is a s problem .And people use fuel Additives sometimes to clean carburetors.
The cheaper fuel with ethanol now and then can help in that sense
 
Ethanol free 90 is obtainable near me but its far enough that I fill 5 gal gas cans.
I use it exclusively in the '78 XS650 and a '79 Triumph Spitfire (car).

Ethanol will harden rubber like fuel hoses, boots, petcock diaphragms.
Plus any of that ethanol vapor gets to the diaphragms, who knows if its going to cause cracking.
 
AI is just trawling the net, albeit faster than you or I could, and presumaby summarising what it finds
It’s my understanding that Google AI is about 80% accurate at this time. The AI that I’m working with on the job is closer to 90%. I’m sure we all remember “Ask Jeeves.” I remember that working well.

Anyway, I opened the gas thread with AI prompt just for fun after the Ozark gathering.

On a trip almost two years ago I put E0 in my bike that was very old. The engine quit every time I came to a stop. Then, I ran out of gas on the Natchez Trace. That taught me first hand to buy gasoline from places that sell a lot of it.
 
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That was a joke BTW - plenty opinions out there for the AI to summarise.

Kinda my point in a way. But why do I need to ask my AI if it is going to use XS650.com to give me the answer. And my search engine quoted Marty's thread for me to view, literally an hour after he posted the thread
 
I put the same question on DUCKDUCKGO.

For a Yamaha XS650 (classic air‑cooled 2‑cylinder carbureted engine), use:

  • Unleaded gasoline, 91 octane (RON ~95 /AKI 91) as a safe default for stock engineswith mild timing/compression.
  • If your model has higher compression oryou’ve advanced ignition timing, use 95–98 RON (mid‑grade to premium) to avoidknocking.
  • Avoid ethanol blends above E10 ifpossible (E10 is generally tolerated butcan cause corrosion, fuel‑system swelling,and carburetor issues in older bikes). Useethanol‑free or E5 where available.
  • Add a fuel stabilizer and a corrosioninhibitor if the bike sits for weeks/months.
  • For winter or long storage drain carbs oruse a stabilizer; for daily riding regular 91octane + ethanol‑free when available isfine.
If you want, tell me your bike year and whether it has any engine modifications and I’ll give a specific octane recommendation.

(Here are related search terms for further reading.)
 
I also asked for ethanol effects on vintage carburetors.

Ethanol can cause significant corrosion and damage to vintage motorcycle carburetors, as it is corrosive to materials like aluminum and brass commonly used in these components. Additionally, ethanol attracts water, which can lead to phase separation and further complications in the fuel system.
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It’s certainly not useless information. Nice it booted the source.
 
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