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Fuel octane , ETC..
Posted: Sun Jun 03, 2007 9:05 am
by kantuckid
I am bringing back an old thread since$gas$ has gone through the roof. I have used 87-89-92 and so on in R1100 and R1150 with no noticeable difference to my ears. I Have also used lots of 87 in the 325/330 series cars. ( My local fuel stop has quit carrying anything but 87 lately! )What are some more recent experiences with various fuels? I have to say that I have poor hearing and wonder if I could be missing a ping???
Posted: Sun Jun 03, 2007 10:45 am
by Oilhead
My '02 RR pings sometimes in 6th gear if I accelerate full throttle even on flat pavement and at speeds well above 55 mph even if I use 93 octane. So using 89 or lower is totally out of the question and I also have to go to gas station with separate hoses so I don't get about a gallon of the cheaper stuff. The bike is maintained meticulously by yours truly and all engine specs are right on.
Believe me. I am a true advocate of "using the the lowest octane that won't make the bike ping" group as that yields the best performance. and if I could use 89 as per stated on the gastank, I would use it. I use 87 in my CBR600RR and KLX250S and it performs flawlessly.
Posted: Sun Jun 03, 2007 12:30 pm
by challey
I often use 87 octane in the cooler months, usually alternating every other tank with 89. No ill effects. Switch to 89 for the warmer months. Once or twice during the summer at 95F+ temps. I've gotting some pinging with the 89, which was easily cured with a tank of super.
I've lost something like 40% of my hearing over the years but engine knocking & pinging sounds are pretty noticeable.
Charlie
Posted: Sun Jun 03, 2007 2:31 pm
by Oilhead
challey wrote:
I've lost something like 40% of my hearing over the years but engine knocking & pinging sounds are pretty noticeable.
Charlie
I have very good hearing but with the earplugs in and a full face helmet, sometimes the minor pingings are very hard to hear.
Posted: Sun Jun 03, 2007 4:32 pm
by ASQTec
Mine pings a bit on heavy acceleration with 92 or 93 octane, and pings like a mother with 91 octane or less. My old H-D FLHTC has the same taste for gasoline. The outside air temp makes no difference, although I usually don't ride when the temp falls below 40F.
Luckily, my 4 cylinder Jeep Liberty runs on anything, so I don't feel so bad paying over three bucks a gallon to fuel the bikes. It could be worse.
Posted: Sun Jun 03, 2007 8:40 pm
by DSKYZD
You can feel the pings as much as hearing them. As stated above under heavy throttle, it's like a click or ticking in the engine. I wear ear plugs and can still notice when it happens. Like others I use the higher octane when the weather warms up.
I also run 4 oz of Seafoam in every 3rd tank or so. You can buy Seafoam at Autozone.
DSKYZD
Posted: Tue Jun 05, 2007 6:34 am
by Arbee
In Australia 91 RON is minimum, everyone uses 95 RON Premium as
called up and sometimes 98 RON octane if you pull up a the wrong
pump and cant be stuffed moving.
Posted: Tue Jun 05, 2007 10:10 am
by gregor
In UK 95RON is the minimum; not sure how octane is defined in USA. Think it is different.
97 or 98 octane (RON) is available also in the UK and is ~ 6p (12c) a litre more. Intended for vehicles with automatic ignition management, like hot Subarus, when a lot of extra power can be liberated.
Posted: Tue Jun 05, 2007 10:25 am
by MikeCam
US uses an average sample of RON and MON. So roughly, our octane is the mid point between readings or about 5 points lower than corresponding RON.
BUT we also offer (require) regional/local blends that change the effective performance (not captured in the octane measures). Such things as oxygenation and ethanol have various effects on engine performance and the ECU ability to adjust to conditions.
Back to the original question -- I'd always use the highest grade I could find and feel 'good' 'okay' 'justified' 'safe' 'reasonable' about price.
Others argue that you can safely use the lowest grade (87) until you detect the ping or knocks.
Posted: Sun Jul 08, 2007 7:28 am
by Beemeridian
456
Posted: Sun Jul 08, 2007 7:52 am
by mcollect
I think it has to do with the density of air. In colder temps there is more O2 per cc then in hotter weather. Of course I'm not a physicist so someone can always correct me.
Posted: Sun Jul 08, 2007 1:32 pm
by hank
How much is a gallon of gas in the U.S.A?
Hank
Posted: Sun Jul 08, 2007 1:47 pm
by kantuckid
I live in the eastern part of KY -also called the Cumberland Plateau. We have a local gas war(2 stations) that has resulted in $2.57 for 87 octane, while nearby it is from $2.67 up to $2.95 depending on all the BS reasons we are given for the variations-of course this is often changed in the middle of a truckload based on a phone call from above. One of my daughter-in-laws says it was $2.46 in SC last week which is said to be the lowest price in the USA @ this time.For you that are younger and live outside the USA I will pass this on-gas was 17.9 cents per gallon during my entire childhood and when I moved from KS to KY in 1973 it was 24.9 cents in KS and 37.9 in KY when I arrived . The private theory I have held onto as to fuel being higher in KY for the first 30 yrs I was here is the close proximity to the (former Ashland now Marathon) refinery as a controlling factor. Another factor (in answer to the UK gas $ question) is that each USA state has a road fuel tax which varies considerably while the federal tax is always the same. For truckers there are several other fueling factors as well-it gets complicated on that issue.Mentioned above in this thread is the fuel formula and understand that there are various state and city regulations that result in a multitude of formulas and the fuel transportation and refining nightmare that results.
Posted: Sun Jul 08, 2007 3:13 pm
by OU812
Today in the Chicago Suburb, it was $3.41 for 93 octane. We get screwed by far the most on taxes, except for the downtown folks, $3.99, who don't even get a reach-around with every fill up.

Posted: Sun Jul 08, 2007 3:21 pm
by def38
hank wrote:How much is a gallon of gas in the U.S.A?
Hank
Here in the Houston TX area, for the highest octane?, about $2.98/US gallon currently. But, we are in the lower range of fuel prices here in SE Texas...about $0.15 more on average across the US.
Posted: Sun Jul 08, 2007 3:24 pm
by def38
Beemeridian wrote:Why does a higher ambient temperature dictate the need for a higher octane?
or rather,
why does an engine ping when using lower octane at higher ambient temperatures?
Combustibility of the fuel and the propensity of lower octanes to auto ignite and burn in an uncontrolled manner....but, that is the quick and dirty answer...Google detonation and other similar subjects for more detail.
Posted: Sun Jul 08, 2007 3:36 pm
by Beemeridian
6798
Posted: Sun Jul 08, 2007 4:00 pm
by def38
kantuckid wrote:One of my Mentioned above in this thread is the fuel formula and understand that there are various state and city regulations that result in a multitude of formulas and the fuel transportation and refining nightmare that results.
About 170+ different local and regional gasoline blends mandated across the US by the politicians who rule over such things and who, by-the-way, don't know a wristwatch from a wristpin. And yes, this nonsense of botique fuel blend stuff does add cost to the motor fuel we buy. For example, two gas stations across the street from one another may be required to sell different blends...a nightmare for the distributors.
Posted: Sun Jul 08, 2007 4:09 pm
by def38
Beemeridian wrote:EXCUSE ME, GENTLEMEN! Now, may we all please return to pursuing the object of my theft as Def38 has so kindly enjoined. Thank you.

Can somebody tell me, is this fellow trying to make me angry or is he attempting a compliment??!!#$*&!??...

Posted: Sun Jul 08, 2007 4:41 pm
by OU812
def38 wrote:Beemeridian wrote:EXCUSE ME, GENTLEMEN! Now, may we all please return to pursuing the object of my theft as Def38 has so kindly enjoined. Thank you.

Can somebody tell me, is this fellow trying to make me angry or is he attempting a compliment??!!#$*&!??...

I am completely lost....
