VFR's and cheap gas

I ran 20,000 miles worth of 87 through my ACE when I had it. The explanation of octane ratings and their effect on an engine should be in the man bible, we'd all be better for it. :biggrin: I've been trying to convince my Pop for three years that he's wasting money putting 93 octane in his vehicle....a friggen' Carolla of all things!

 

Sometimes, Nozzle, things just arent as simple as 2+2. See Eddie's post.
I'm using the 85, thanks for the explanation Eddie.

 

Ugh! In this country you can't find anything below 95 octane.. Actually, all you get is 95 or 97. I assume the bikes sold here are tuned for 95 then.. My previous bike (Hyosung gt250R) enjoyed the 95.. -turgut

 

In most countries (including all of Europe and Australia) the "headline" octane that would be 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, this means that the octane in the United States will be about 4 to 5 points lower than the same fuel elsewhere: 87 octane fuel, the "regular" gasoline in the US and Canada, would be 91-92 in Europe. However most European pumps deliver 95 (RON) as "regular", equivalent to 90-91 US (R+M)/2, and even deliver 98 (RON) or 100 (RON).:biggrin:

 

I am all for babying my baby, but why is it that you think the higher octane would be better? Especially if you admit you can't tell the difference? 0.10 - .25 cents a gallon is not much, but if it doesn't do any good, than why do it at all?

 

What if you own a vfr and your ignition is not set up to advance the timing for 93 and all that ends up happening is you get incomplete combustion because 93 does not burn as well and you just end up building more carbon in the motor?

 

More carbon in the combustion chamber causes increased pressure and now you have to run higher octane to prevent pre-ignition.

 

I have a friend who runs 44 convience stores. He says where you buy gas is much more important than the grade. The gas ALL comes out of the same pipeline. The only difference is the additives that are put in it as the tanker truck fills up. Different brands simply use their own additives. How it is stored and how long it is stored at the station is the biggest factor. I see him going through a lot of pains to keep fresh gas in the ground, and computers that check for water etc. Your best bet are large stations which sell tons of gas, and don't sit on it for days or weeks.

 

Jethro is completely right. I'm studying engine science and here's my 2 cents:
Engine octane rating is a method (sometime inaccurate) of determining a fuel ability to resist autoignition. The engineers at Honda gave a recommended octane rating for use in the bike. However, that recommendation requires some assumptions about how the bike is used. If the bike is being worked hard, its cylinder wall temperatures will increase significantly promoting autoignition. Therefore, for the more sporting riders, I would suggest a midgrade fuel ~90.

More generally, it is completely possible that the engineers at Honda choose to allow a mild autoignition when recommending the 87. Pre-detonation is probably a better term for this phenomenon, as only a small portion near the rings ignites prematurely. This type of auto-ignition typically does not result in catastrophic failure of the piston, but could reduce the life of the cylinder sleeves and rings.

Moreover, mild autoignition does not always result in the typical ping or knocking noises associated with autoignition. Performance should not be a criteria for the use of fuel either. In fact, autoignition often improves power output if the timing is not drastically affected. Some drag-racing vehicles allow autoignition to improve performance while accepting the decrease in longevity.

My recommendation, if you tend the push the bike for extended periods and plan to keep it for a long time, use fuel slighly better than recommended.

 

I can tell that this is a mistake but here I go anyway!
As many have stated it is important to follow the owners manual. I recently sold a 96 VFR with 50,000 miles I ran 87 in it and it still purred like a kitten.
Many have come close to the reasons for the octane differences and the similarities in performance. This is what I have learned:
The higher the octane rating the higher the flamibility of the fuel if all else is equal. However all else is not equal between 87 and 92 fuels.
Many have pointed to the fact that higher octane fuel is designed for higher compression engines there in lies the difference! The higher octane is need to combat the anti-ignition properties of certain anti-knock additives. This is why 87 and 92 get comparable performances.
I would think that 11:1 would be high compression but I guess it is not since 87 has no ill effects on my ride.
Lastly, if your bike was knocking, pinging, or pre-igniting (almost all the same) you would know it. It is loud enough for a layman to know that something is wrong and performance will suffer. Don't take my word for it, talk to a mechanic if you think that you are suffering from a knock.
Run what you please and sleep well about it at night! I will continue to run 87 and sleep just fine.

 

eddie your buddie is right on, i would also avoid filling up at a station the same time the tanker truck is filling the station tanks, thats when all the crud from the bottom of the tanks get stired up

 

So when I store my bike for the winter, what octane should I put it with the fuel stabalizer? Is higher octane stable longer?

 

Neither should be stable longer but lower octane ignites easier, so make your own decision.

 

Try Wasps nest Haha Mercy and I've proven it to a many surprise, that the good stuff is the stuff to use. period, end of discussion LOL use what you want. but don't come to me later going huh?

 

personally i use 91. id rather be safe than sorry since i dont have my PC3 tuned and have a better flowing exhaust (hopefully catless soon too), and a better flowing intake.

my GTO also only gets 91, but once and a while will get a couple gallons of 109 since it runs a lot better on 93 than it does 91. i believe the manual reccomends 93, but requires premium. it can still use a lower grade, but they reccomend you put premium in it asap. that thing has only seen 89 ONCE and it was cause the station was out of premium, so it got a couple gallons of 89 to hold it over till blythe.

 

new thought,

my friend use to work with chevron & he was contracted to get samples from production on loads going out from the plant.

He told me that the octane level is the "AVERAGE" rating & that it can be under or over 1 to 3 points.:frown:

So with that being said, your 87 could be down to 86 or even 84 out:

So on long distance riding I alway's put in the highest rating, & for the track & around town, county short hops (I mix 2/3's pump to 1/3 VP) the 88 mid grade here in utah with the 98 VP unleaded gas to get a more "stable octane rating". my bikes run great & when cking the plugs & valves, they alway's look pretty & new (as in perfect colorization on the plugs).
I also run my bikes on the Dyno to jet (carbs) & map (fuel injected) to make sure they are not running lean or rich.

So motto here is run what you want & or feel confortable with, no damage no foul :wink:

 

then add in if you use a pump with just one hose for all grades, and no matter what you choose, you are getting a little of what the last person chose. So your 4.5 gallons of super, might be 3.5 - 4 gallons of super, and the rest the regular stuff! Ohh, the horror. Depending on pump design and proximity to the tanks.