i'd kill to get ethanol free. it's prettymuch impossible now though.
i just hope the US does not move to E15...as most cars/bikes will not be able to handle it. say goodbye to your fuel system and gaskets
Regular Unleaded vs Premium Unleaded?
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i just hope the US does not move to E15...as most cars/bikes will not be able to handle it. say goodbye to your fuel system and gaskets
dndfindley
New Member
You said it exactly. There is absolutely NOTHING to gain from using premium fuel in a car, truck or motorcycle, that calls for regular gasoline. Unless their vehicle has been modified anyone who says they notice a difference is only imagining it. The FZ6R calls for regular - why pay a lot more for gas that is doing nothing to improve your performance. The wife's Yamaha T-Max on the other hand calls for premium fuel. It was designed that way and Yamaha says use it so we do. David
If your engine calls for 87 octane, that is what you should buy.
a) The "regular" tanks are used far more often, and have a far greater chance of containing fresh gas (less water in the tank).
b) Ethanol has a higher natural octane rating than gasoline, thus it makes a relatively cheap octane booster.
c) Gasoline has a greater energy density that ethanol. Thus, Ethanol-free gasoline has a greater energy density than the ethanol blends (E10).
Thus, by buying premium (91 or 93 octane), you are buying something with a reduced energy density (less energy in a given volume) that requires a higher temperature (compression) to ignite. A higher octane rating can be accomplished with more ethanol. It can be accomplished by diluting the gasoline with water. Duh.
Higher octane = higher price.
Higher octane = reduced energy density.
Greater ethanol percentage = reduced energy.
But since premium has a higher price and margin, the gas companies have spent decades (all of my 55 years, for sure) convincing the gullible that "premium" is better than "regular", that by buying "premium" you are more like a Vanderbilt than that dumb loser buying "regular." That is WHY the higher octane fuel is called "premium." Don't fall for it.
For a neat chart of this:
Octane rating - Wikipedia, the free encyclopedia
Ethanol-free, 87 octane is the best for our bikes.
Ethanol-free gas stations in the U.S. and Canada
Bob
a) The "regular" tanks are used far more often, and have a far greater chance of containing fresh gas (less water in the tank).
b) Ethanol has a higher natural octane rating than gasoline, thus it makes a relatively cheap octane booster.
c) Gasoline has a greater energy density that ethanol. Thus, Ethanol-free gasoline has a greater energy density than the ethanol blends (E10).
Thus, by buying premium (91 or 93 octane), you are buying something with a reduced energy density (less energy in a given volume) that requires a higher temperature (compression) to ignite. A higher octane rating can be accomplished with more ethanol. It can be accomplished by diluting the gasoline with water. Duh.
Higher octane = higher price.
Higher octane = reduced energy density.
Greater ethanol percentage = reduced energy.
But since premium has a higher price and margin, the gas companies have spent decades (all of my 55 years, for sure) convincing the gullible that "premium" is better than "regular", that by buying "premium" you are more like a Vanderbilt than that dumb loser buying "regular." That is WHY the higher octane fuel is called "premium." Don't fall for it.
For a neat chart of this:
Octane rating - Wikipedia, the free encyclopedia
Ethanol-free, 87 octane is the best for our bikes.
Ethanol-free gas stations in the U.S. and Canada
Bob
Why I even bother chiming in is beyond me, but I guess I just can't help myself sometimes.....and in the interest of keeping everyone honest. Here is the direct quote from the manual so feel free to use premium and you may actually be feeling a difference unless "findley" has ridden your bike in which case he clearly knows best:
"Your Yamaha engine has been designed to use regular unleaded gasoline with a pump octane number of 86 or higher, or a research octane number of 91 or higher. If knocking (or pinging) occurs, use a gasoline of a different brand or premium unleaded fuel. Use of unleaded fuel will extend spark plug life and reduce maintenance costs."
Consider my use of 87 in the prior post to be inaccurate. 86 it is! 87 is the lowest available around here, although I bought 86 in New Mexico last week. Last time I bought anything higher than regular (86/87 pump octane, (r+m)/2) was for my wife's Miata in the mid-90s (cause I'd added a supercharger to it).
Thanks, Sammy.
Bob
Thanks, Sammy.
Bob
Like I said, unless you experience pre-detonation/pinging there is no need to use premium and is just a waste of money... Higher octane does not mean better performance. Why people think higher octane gas is means better performance is beyond me. It is simply a rating of octane/combustion. I guess the word "Premium" makes people think its better... Oil/gas companies LOOOOOOVE you! Their choice of marketing works apparently.
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alaskanflyboy
Premium Member
My memory may be a little rusty, but I'm hoping I remember most of the info from my aircraft systems class and apply it. Feel free to correct me if I botch something.
Use of the recommended minimum octane is fine, and what I use. If you experience engine knock (officially known as detonation), you would be better off buying a higher octane, as it requires a higher temperature to ignite which should prevent detonation. Higher octanes typically burn more evenly, but also at higher pressure. These engines were designed with 86 octane in mind, so it all the timing and other parameters are centered around that fuel. So, as the manual states, we're fine with regular unless our engines start detonating. Of course, never use less than 86 if you somehow find anything lower as you start running the risk of detonation.
Great article in Super Street Bike this month about regular unleaded vs. premium unleaded, with dyno tests and graphs and all that, but the conclusion is about the same as alaskanflyboy's.
More Octane For More Power? | Mythbusters - Super Streetbike Magazine
More Octane For More Power? | Mythbusters - Super Streetbike Magazine
Really good article, explain it all. Maybe this is why here in S. Florida I notice the bike running better on premium. It's so hot. Just a sharper throttle response, but I don't feel anymore power.
The thing I can really feel is when I sit in traffic in Miami and it's so hot outside that my shoes are sticking to the ground. The bike doesn't like it at all.
The main difference between 87, 89, and 91 Is stability. 91 will not give you anymore power over 87 unless your engine has a high compression ratio. Using 87 octane in a high compression engine can cause the fuel to pre-detonate before the spark plug goes off causing loss of power and possible engine damage. 87 is less stable than 91 and that is why it can pre-detonate. Because 91 is more stable it is commonly used in high compression ratio engines. The Engine in our FZ6R's has a fairly high compression ratio and that is why premium fuel is recommended.
"Stability" isn't the word I would use. The main difference between them is the FLASH POINT. That is the temperature where combustion occurs.
In a way you are correct; if the fuel flash point is too low for a particular engine, it will detonate pre-ignition and bad things happen. In this case, yes, lower octane fuel is less "stable" in that engine. If the engine was designed to operate on 87 octane (as the FZ6R engine is I read nothing in the manual that says premium is recommended) then the 87 octane is no less "stable" than 91 in that engine barring extreme circumstances such as extremely high temps. In that case, you have multiple things to consider.
Compression is a big part of the equation, since temperature increases with pressure, but not the only one. The engine was "designed to use regular unleaded gasoline with a pump octane number...of 86 or higher". Directly from the owners manual. It goes on to say if knocking or pinging occurs use a different brand or premium.
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Thank you... I don't understand why this is so hard for people to comprehend...
:banghead:
alaskanflyboy
Premium Member
I believe you're referring to pre-ignition, which is similar but different from detonation. But it is another thing higher octane can help alleviate. Pre-ignition is as you describe; hot spots in the engine light the fuel before the sparkplugs do. In aircraft, this is often from carbon deposits building on the cylinder walls that effectively create hot coals. Detonation comes from an uneven burn of fuel caused by either uneven mixing of the fuel air mix, or incomplete burn that ignites as it enters the exhaust phase as it passes the hottest part of the engine.
Another thing to consider is that sparkplugs also play a factor in how an engine reacts to fuel. It's not just engine compression, but how hot the sparkplug is designed to run. Compression heats up the mixture, but the plug touches it off. I've also seen nothing that recommends premium fuel for the FZ6R other than in the case of abnormal combustion, which typically is a sign of other factors than just fuel octane.
sbhoopsfan
New Member
From Jersey too, use premium as well.
I use premium fuel always, especially when your running e-10, star-tron enzyme fuel additive has worked well for me, it's what my dealer recommends and I have had good luck with it. In my opinion less than a dollar difference between regular and premium is well worth it for a full tank of higher quality fuel but I'm kind of OCD about my bike. Note: I use the star-tron additive a couple times each year to clean things out, I do not use it with every fill-up because running additives constantly through an engine makes me nervous.
How is it higher quality fuel? Please explain
18 pages.... it will never end....
"but it says premium, and it costs more, so it MUST be better"
I converted mine to jet fuel! Work ok but people start complaining that there eyes are burning when they follow me. I just order 4 can of 18:1 compression ratio. I want to convert it to Diesel or Vegetable oil. There's a 5 Guys burger joint close from where I live... I can get the used oil for free!:wav:
SampsonNation
Member
Ah screw it. I'm staying with 87 . If it's designed for it, I don't care what the other equations are. Black and white.. It can handle it fine.
. If it's designed for it, I don't care what the other equations are. Black and white.. It can handle it fine.peterstoker
New Member
what is the highest octane you have over there in the US? by the sounds of it its only 91, here in oz thats our regular and our premium is 98 and they even sell 101 in a few places but thats very rare!
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