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Whilst out riding with a couple of mates this weekend we had cause to fuel up. I put in standard unleaded (92 Ron)into my 02TBA much to the digust of my fellow riders. I would welcome comments as to whether I should be fuelling with the higher grade unleaded and if I did would I need to adjust carb settings. I have been running on standard unleaded since I bought the bike 3 months ago. On another note I have changed to TOR exhaust and blanked of the AI and when I stop after a run and switch off The engine gives a little blow right at the finish, just like if you blow and oil lamp out.....????any ideas???

normal unleaded 95 no point to fill up with 98 expencive one!!!

Wheres Bigbill? He loves octane questions!! LOL

I don't know if your rating is the same as ours over here. Maybe Bill can enlighten me on that point but I recently went to the mid grade here due to cost and have noticed no performance issues,no pinging or anything and mid grade here is 89 octane. I always ran 92 or 93 here until this year. Octane rating is the rating that indicates the fuels resistance to preignition that's why you need it in higher compression engines but our bikes are not high compression so it's not needed. You should need no carb changes if you run the next grade up.

I ran regular grade fuel (your 92Ron) until the BB (about 4.5 years). Never had a problem. If you are not pinging, tell your mates to stow it.

Thanks guys that has put my mind at rest, just wait till I see those mates again, they can buy the coffee for trying me to pay more for my fuel.

Right here Ian . I was at Church.

You handled it pretty well.

I'll just add my standard:
Octane rating is not a measurement of power potential.
It's not a measurement of quality.
It's resistance to ignition. Period.

I think I may just type up an explanation and save it so I can copy and paste every time this question comes up.

Thanx Phil and Bill. I'll have to read up on that when I get a chance.

I used regular for a few tanks. Near the end of the second tank, my wife noticed a "high pitched knock". I asked if it was a pinging sound, and she said "almost". Since I have a high frequency hearing loss, I assumed it was the fuel. I've burned mid grade ever since.

Man, you guys are cheap... At $3 a gallon, and $0.30 difference between the low grade and high grade, you are talking about a whole dollar difference per fill up. What did you pay for your last cup of coffee?

I can see being cheap on things like chome and carbs... ahem...

I run high test now, Erwin but only because of the BB.

Cowboy, if there's no performance/reliability reasons to put the higher/highest grade in, why do you?

I like to use it all to keep my engine guessing!

Oh, Phil. Down here we throw money out the window to see how far it flies.

My point was/is, its a buck. So much to do about a dollar when most people pay $4.50 for coffee. Still beans and hot water (and a whole Lotta caffine). Now ya'll don't get on me about good coffee and swag coffee. I like good coffee, too. I even own, and use, a grinder.

Post Script, I did learn about octane ratings here, so thats a good thing. My questions back to ya would be what about carbon deposits? My understanding is that the high grade fuels succumb to higher refinement processes are therefore cleaner burning and typically leave less carbon residue. Is this folly?

I actually started using regular right after but she pinged so bad, I went to mid-grade. Still pinging and only high test stopped it. Besides, I make so much money I have plenty for beer!!

I agree with Phil. I used to run 10.5:1 pistons in the old bikes and you pretty much have to run premium to prevent the pinging.

As grzegorz said normal is 95 RON and that's what the book says it should be, as a minimum.

I tend to use super (if I can afford it) as he seems to like it better...and it makes him go faster. But never the branded stuff (optimax excellium or anything like) that's just too expensive.

How is that pronounced again Bill?

Dang lemmings!

Have you tried mid-grade for a couple of tanks? You may not need hi-test....

You know.... those cute little blue ones......

I filled up with 87 yesterday and rode about 100 miles. No ping. I was using 89.

I've always felt that there was a certain machoism by be required to buy High-Test, but now the price of fuel has me buying mid-grade and it's working just fine.

Gerry

I recently left a 30 year job as a gasoline transporter. Some might be surprised to learn who sells what gas to whom at the loading racks. We used to lift brand A at brand B's terminal, all the way through brands L, M, N, O, P, 7 days a week. In the petroleum business, these product swaps are known as "throughput arrangements." (The gas guys can't say things simply, like "swapping product" and so use fancy terms like throughput arrangements.)

There are exceptions to this practice, where for instance brands P, Q, and R will only sell their own products at their gas stations.

Octane rating only indicates a fuel's ability to resist knock. It really has nothing to do with level of quality. High octane fuel won't make a vehicle designed to run on 87 octane run any better or faster. Even the fuel guys will admit to that.

A dollop of trivia - by definition, there is no octane rating higher than 100.

Another thought to ponder - when product is moved up the pipelines, there is no device to seperate the products in the pipe. 12 miles of gasoline will have 10 miles of home heating oil on it's tail. Where the two products meet there is a predictable amount of co-mingled product.

Guess where that co-mingle goes? Let's just say, dilution is the solution.

Here in Iowa, officially "The Tall Corn State" we love our ethanol. But, as was mentioned in the link bigbill included, ethanol blends contain less potential energy per gallon. Over the last few years I have been mostly filling up with the non ethanol 91 Octane for two reasons.

First, I get a pronounced ping under hard acceleration with 87, 89 takes most of it away but on a hot day and moving like a striped a$$ed ape it may still occur. 91 Octane eliminates the ping altogether.

Second, on those occasions when 91 Octane is not available and I fill with the lower octane ethanol blend I usually get fewer miles per gallon. At first I ascribed it to the usual variations encountered such as speed, traffic and wind. But, it has proven to be a constant over the more than two years since I first noticed it. The non-ethanol fuel seems to get about 5-10% more mileage. When I’ve filled with non-ethanol fuel I normally go 10-15 miles further before switching to reserve than when I fill with the ethanol blend.

I haven’t noticed this difference in my car or truck. I’m guessing the reason is that I normally push the bike much closer to it’s performance limits, while when I’m forced to use the four wheeled vehicles I’m satisfied to simply plod along.

Bucky since you seem to be in the know, is it true that BP and Hess sell little or no middle eastern fuel?

I thought AV gas and such had octane ratings higher than 100?

I know I'm splitting hairs a bit, but octane is the measurement relative to the proportions of iso-octane and n-heptane. An 87-octane gasoline, for example, has the same autoignition resistance, or octane rating, as a mixture of 87% by volume of iso-ocatne and 13% by volume of n-heptane. The octane ratings of n-heptane and iso-octane are respectively exactly 0 and 100, by definition.

Aviation and racing fuel 'octane' numbers are an accepted misuse of the word octane. They get those higher than 100 numbers via Benzene, Methane, Ethane, Toluene, Xylene.

It would be a bother to say "well it's like 100 'octane', but 13 clicks better," and so 113 octane it is. In the abstract, it's not too far from "Kleenex" meaning facial tissue.

Tune in again next week folks, for yet another episode of Bucky's Boring Fuel Facts!

Personally I enjoy it. I am always looking to learn useful things. I believe it to be a great help to understand the octane rating. Without what Bill taught me about it I would never have tried a lower octane fuel. And he didn't just leave it as his word he had posted web page info to read to back it up. I found that a very informative read. And Now Bucky too has given me info I didn't know.

Thanx guys.

Mark - no pigs run the pipes. There is surprisingly very little co-mingle, and it is of no concern that a consumer might ever get some diesel or kero in their gas. The only reasonable way that would occur is if the delivery truck made a mis-delivery at the station. Ultra Low Sulfur Diesel is another story. Last I knew, it had to come off the pipe at Fairfax, VA to journey any farther north, in order to remain at it's pristine condition of less than 15 ppm of sulfur. Sulfur apparently lays in the nooks and crannies in the pipes and pumps on the trip northward.

Another fun fact - The over whelming majority of fuel in the northeastern US comes up one pipeline from Houston to NY Harbor. A hurricane season or two ago, when Houston was looking at a potential Katrina sized event, those of us in the northeastern fuel slingin' market were crappin' peach pits. If Houston ever goes down, the Northeast would be out of fuel. There is very little extra storage capacity here. Building reserve fuel storage facilities falls into the NIMBY law suit black hole.

Dog - Hess is well known to use very little middle eastern oil. They're said to use primarily only their own product from their own wells. I would imagine they buy some middle east product here and there when the market price is right, but I'm not sure exactly how that works, and they aren't going to tell us either. It wouldn't surprise me if if BP is the same, as I believe they work the North Atlantic region pretty hard, but I don't really know.

More trivia - I would advise to avoid fueling up while the truck delivers at the station. Dumping fuel could well stir up the small volume of water (from condensation) that is on the bottom of most underground storage tanks. Water is a known and managed commodity in USTs, and is usually of no concern as the pick up tubes are well above the tank's bottom, and many gas stations pumps have water occluding 'Hydro-sorb" type filters inside their shell, but I feel better waiting a half hour to let the water settle. Call it superstition I suppose.

Working with gas station owners for years, I can say that most I know want to do a good job, and want to sell good product. They don't want quality issues any more than we the consumers do. They are not the ones reaping the big profits when the prices spike. On the contrary, they often lower their mark ups to compensate and remain competitive with the station down the street who hasn't taken delivery of the higher priced product, and actually lose money. Fuel is a traded commodity in today's market, with prices that change throughout the day. The load of fuel purchased today could cost 5 or 10 cents a gallon more than the load purchased yesterday. In my limited opinion, price gouging is not an issue where competition among stations exists. To have the states get involved with gas pricing would only serve to cause problems.