Which fuel?

[Capo79]

Funny thing... Here in Norway you don't get gas with an octane number below 95. One gas company operated with 92 unleaded for a while, but I believe that didn't sell much, so they gave it up.

The quality of the fuel itself shouldn't be inferior to what you guys have in the states, but I guess there's just been a tradition for higher octane fuels in Europe in general.

 

[VWci]

In the states they use different method to determine octane ratings. I think 87 equals to europe's 95...

 

[04fizzer]

In the states they use different method to determine octane ratings. I think 87 equals to europe's 95...

Exactly. The octane rating they're talking about is the US (R+M)/2 method, compared to the RON method used in Europe.

 

[Capo79]

Exactly. The octane rating they're talking about is the US (R+M)/2 method, compared to the RON method used in Europe.

Ah... Then I learned something new today! So what you're saying is that 92 octane in the States would roughly equal 98 in Europe?

By the way: In the equation above, what varables are the letters symbolizing? And what is the "RON"-method?

 

[SirIsaac]

Ah... Then I learned something new today! So what you're saying is that 92 octane in the States would roughly equal 98 in Europe?

By the way: In the equation above, what varables are the letters symbolizing? And what is the ''RON''-method?

From Wikipedia:

Measurement methods
The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions, and comparing the results with those for mixtures of iso-octane and n-heptane.

There is another type of octane rating, called Motor Octane Number (MON) or the aviation lean octane rating, which is a better measure of how the fuel behaves when under load. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, a higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. Normally fuel specifications require both a minimum RON and a minimum MON.

In most countries (including all of Europe and Australia) the ''headline'' octane rating, shown on the pump, is the RON, but in the United States, Canada and some other countries the headline number is the average of the RON and the MON, sometimes called the Anti-Knock Index (AKI), Road Octane Number (RdON), Pump Octane Number (PON), or (R+M)/2. Because of the 8 to 10 point difference noted above, the octane shown in the United States is 4 to 5 points lower than the same fuel elsewhere: 87 octane fuel, the ''regular'' gasoline in the US and Canada, is 91-92 in Europe. However most European pumps deliver 95 (RON) as ''regular'', equivalent to 90-91 US (R+M)/2, and some even deliver 98 (RON) or 100 (RON).

 

[04fizzer]

Ah... Then I learned something new today! So what you're saying is that 92 octane in the States would roughly equal 98 in Europe?

By the way: In the equation above, what varables are the letters symbolizing? And what is the \"RON\"-method?

The r is the RON (research octane number)
m is the MON (motor octane number)
Octane rating - Wikipedia, the free encyclopedia
Google Answers: Octane formula

Essentially it's the average of the RON and the MON.

 

[RedX7]

There was a huge thread like this on SBN a long time ago. My favorite quote was, "When you go to fill up your bike ask yourself, "do you know more about it than the Yamaha engineer who designed it?""

 

[billm]

When I picked up my bike from it's previous owner I asked him what fuel he used & he said he's always put "High Test" in it. Well, not knowing any better & figuring this is a high-tech engine (& my last bike was a Sportster - not high-tech) - I filled up w/the same the first time. Then I stumbled onto this Forum & one of the threads at that date was the use of premium fuel vs. reg. Then I downloaded the MOM & I've never used premium again!:Flash:
BTW - it ran the same w/either fuel!!

 

[interactive3]

As Wrightme43 said, 87 actually burns hotter than 91. Because it burns hotter, it actually makes more power as well. The only advantage to higher octane fuels is it's tolerance to pre-detonation, which is why it is used/recommended in higher compression engines. The FZ6 was designed to run on 87 and will get the best performance out of 87. 91 octane fuel would be a waste of money and will make your bike run more poorly.

It was my impression that the higher the octane the less pre-detonation AND a slower burn rate. If the burn is extremely rapid (too rapid for the engine design) then it happens while the piston is still near the top of its travel, pushing hard on the piston, but for a relatively short time. It was also my impression that this can cause pinging, since the expansion has no place to go as the fuel out-burns the travel of the piston.

I believe that using a high octane fuel in a engine that was designed for low octane is not a good match because the fuel may not fully burn by the time the piston reaches the bottom of the stroke and the exhaust stroke begins. This taxes the emissions system because the unburned fuel is exiting the engine.

If low octane fuel were actually making "more power" then anyone racing would use low octane fuel, not the high octane racing fuel. It all has to do with matching the fuel to the engine.

I'm no expert though. Please correct me if my impressions are incorrect. Thanks.

 

[colobb]

This is like a dreaded oil thread.

The FZ6 is sold around the world, and designed to run on varying grades/qualities of fuel. Use 87 octane (R + M)/2 -(I've never seen 86), unless, as the owner's manual states, you get pinging/knocking.

Bottom line, its your money and your bike, use whatever fuel you want.

 

[stevesnj]

I have tested all octane levels and brands and mine seems to run best on Sunoco Plus... 89 Octane. I also use Fuel Injector cleaner 2 ounces ever 10 tanks.