Octane

[GAWildKat]

Since I don't have a bike yet I won't presume to jump on the octane thing in relation to bikes.

 

However I've had my 96 caprice for nearly 10 yrs.

My caprice has the same engine that the Vettes and Cameros of the same period.

We bought it with 75k miles, it has just over 155k miles now. All oil changes have been done on schedule, all other maintenance, in relation to driving and operation have been done. What we've learned over the years is as the car has gotten age we've had to increase the octane to prevent pinging and increase economy. The other thing we learned was to use a 4 pronged sparkplug on the car to help with these issues. These weren't things we did overnight, these things were things we learned over the years.

[midnightventure]

I have over 80000 miles on mine and it runs great on regular.

[RossKean]

If it doesn't ping, there is NO value in running higher octane gasoline. The confusion comes about because of definitions used in North America vs elsewhere. The 91 refers to the RON (research octane number) which is NOT the number on the pump in the USA. Read this Wikipedia article:

http://en.wikipedia.org/wiki/Octane_rating

[Scooter Bob]

Mine will turn 70k in a couple days, and has had regular 87 most it's life.

 

When I was dragging a pop up camper around a few years ago, I would run mid grade to reduce the pre-ignition knock when starting out with the big load.

 

And I have no problems with the 10% ethanol either. Doesn't seem to hurt the MPG any. And that's 10% I give to the farmers here instead of the foriegn oil big whigs. It just makes me feel better.

 

And no, I don't want to get into the whole, fuel for the tractor issue.

 

Along the lines of what others have said, not much to gain once the octane is high enough to stop the pre-ignition knock under low speed, heavy load.

 

Just my , Scooter Bob

[ArticusMedicus]

Regular 87 in my 04 I tried a 18 year old McAllen Scotch once.... But the bike didn't like it and fell over stone drunk and got horrible mileage. Damn lightweights!

[elmicko]

I think sometimes it has more to do with the individual personality of the bike. My 86 doesn't really like regular, but runs like a scalded dog on premium while others have the opposite results. Go figure.

[Flyinfool]

It may even be that as some bikes get older that are not driven hard enough to "blow the carbon out" that the compression ratio actually does go up with age. My 88 pings terribly when under 3K RPM unless I have premium in it.

I have never yet hit red line in the 3 years that I have had this bike. The one time that I got close to red line the front wheel came off the ground and scared me.

[Guest Boomerbiker]

I have 25,000 miles on the '06 Venture using 87 octane. Bike runs like a dream. I carb sync it at every oil change, Mobil 1 Synthetic 10W 40.

 

Boomerbiker

[StormRaven]

Since I don't have a bike yet I won't presume to jump on the octane thing in relation to bikes.

 

However I've had my 96 caprice for nearly 10 yrs.

My caprice has the same engine that the Vettes and Cameros of the same period.

We bought it with 75k miles, it has just over 155k miles now. All oil changes have been done on schedule, all other maintenance, in relation to driving and operation have been done. What we've learned over the years is as the car has gotten age we've had to increase the octane to prevent pinging and increase economy. The other thing we learned was to use a 4 pronged sparkplug on the car to help with these issues. These weren't things we did overnight, these things were things we learned over the years.

 

A couple of things I wanted to elaborate on with my wife's post... With the Caprice, I'm about positive that there's carbon buildup on the pistons that's causing pinging with Mid-grade, which is causing the OBD-II Computer to retard the ignition timing to prevent the ping...and thus reducing my mileage to the low 20's (between 21-23 MPG). Going to High Octane will bring that up to about 25-26 MPG. Right now we're running single Prong AC Delco plugs on it at the recommendation of the mechanic... and I'm regretting it. When I had the car running on the 4 Prong Bosch plugs and High octane I was getting between 25 and 33 MPG depending on how often I brought the thing up to 160 MPH. (only once when I had performance tires on her... Last few sets of tires I bought are only rated for 118 so the computer is now shutting off the fuel flow at 110 max.)

 

What I'd like to do once I can retire the baby to part time transport (once I get the bikes) is take off the heads and carbon scrape the pistons. It'll also give me a chance to see how the walls are holding up and see if I need to think about getting a new engine for her (doubtful).

Edited June 7, 2010 by StormRaven

[straycatt]

depending on how often I brought the thing up to 160 MPH. (only once when I had performance tires on her... Last few sets of tires I bought are only rated for 118 so the computer is now shutting off the fuel flow at 110 max.)

 

 

 

Your cars computer knows what the tires that are on the car are speed rated for and limits its speed accordingly???:confused:

[GaThumper]

A couple of things I read on another forum discussing octane.

 

Depending on the location and the station, they may not sell much premium, especially with the higher prices. This could mean that the gas has been sitting in the underground tank for longer periods, and the tank could be less than full lot's of time. This could potentially lead to contamination.

 

Now, I read that on the internet, so it must be true! Anyway it was something that made me think about the fuel coming out of the premium tanks around here.

 

The other thing was more important with the small tanks and (sometimes) one gallon fill ups of the dual sports. If the pump has a single hose switching between all three grades, there is some amount of fuel in the hose that is left from the previous customer. How much, I don't know? But again, it gave me cause to think.

 

As far as my '01 Venture goes, I've put regular in it almost every time and I've never heard it knocking, so I'll continue to run regular in mine.

 

Have a Blessed Day!

James

[StormRaven]

Although the few times I've test driven some newer cadilacs and impalas with the on board computer readouts that have listed tire Type, Performance rating, and pressure... The caprice computer was reprogrammed in-shop (I'm assuming this...though considering that I read somewhere that the 9C1 Caprice [police package] IS supposed to be able to sense the tire performance rating and adjust its top speed accordingly...there's no telling.)

[GAWildKat]

to answer about the gas left in the hose from one person filling up to the next...there's approximately 1 gallon of gas left in the hose after you switch the pump off and hand the hose up. That is 1 gallon of gas you paid for but didn't receive. Now if ppl realized this we might have some outraged ppl out there. Used to you could switch the pump off and drain the hose into your tank to get all the gas you paid for. However once you hung the hose and drove off the gas in the hose would drain back into the underground tank. This only applied to the older gravity fed pumps where the hose is anchored above the pump. Not sure about the newer designs nor the chest high pumps. Only reason I know about this was I worked in a gas station once and the owner used to brag about essentially selling the same gallon of gas over and over and turning a nice profit on a builtin flaw in the pumps. Since I didn't drive (learned to drive at 26 ), it didn't bother me then, now it makes me go hmmmmmm.

[gibvel]

to answer about the gas left in the hose from one person filling up to the next...there's approximately 1 gallon of gas left in the hose after you switch the pump off and hand the hose up. That is 1 gallon of gas you paid for but didn't receive. Now if ppl realized this we might have some outraged ppl out there. Used to you could switch the pump off and drain the hose into your tank to get all the gas you paid for. However once you hung the hose and drove off the gas in the hose would drain back into the underground tank. This only applied to the older gravity fed pumps where the hose is anchored above the pump. Not sure about the newer designs nor the chest high pumps. Only reason I know about this was I worked in a gas station once and the owner used to brag about essentially selling the same gallon of gas over and over and turning a nice profit on a builtin flaw in the pumps. Since I didn't drive (learned to drive at 26 ), it didn't bother me then, now it makes me go hmmmmmm.

 

Very seriously doubt that it's close to a gallon of gas. I turn off the pump, hold the hose up and squeeze the handle every time I fill up. Maybe a quart tops but then I doubt that it's that much.

 

EDIT: Just found an article that states that the American Petroleum Institute says about 1/3 of a gallon is left in the hose after the nozzle shuts off.

Edited June 7, 2010 by gibvel

[LilBeaver]

to answer about the gas left in the hose from one person filling up to the next...there's approximately 1 gallon of gas left in the hose after you switch the pump off and hand the hose up. That is 1 gallon of gas you paid for but didn't receive. Now if ppl realized this we might have some outraged ppl out there. Used to you could switch the pump off and drain the hose into your tank to get all the gas you paid for. However once you hung the hose and drove off the gas in the hose would drain back into the underground tank. This only applied to the older gravity fed pumps where the hose is anchored above the pump. Not sure about the newer designs nor the chest high pumps. Only reason I know about this was I worked in a gas station once and the owner used to brag about essentially selling the same gallon of gas over and over and turning a nice profit on a builtin flaw in the pumps. Since I didn't drive (learned to drive at 26 ), it didn't bother me then, now it makes me go hmmmmmm.

 

Very seriously doubt that it's close to a gallon of gas. I turn off the pump, hold the hose up and squeeze the handle every time I fill up. Maybe a quart tops but then I doubt that it's that much.

 

He does specify that this is for the older style pumps - which I know I have not seen around for a long time.

 

I too push the pump shut off deal while still squeezing the handle and I'd estimate max that comes out is maybe a cup (8 fl oz or ). And that is quite the stretch. I do it because it seems inevitable that some drips out when you shut the pump off anyway and I HATE when gas drips on my painted surfaces.

Just my

[LilBeaver]

...

EDIT: Just found an article that states that the American Petroleum Institute says about 1/3 of a gallon is left in the hose after the nozzle shuts off.

 

So, what is left over and what is actually accessible are two different questions...

[gibvel]

So, what is left over and what is actually accessible are two different questions...

 

I agree with that as well. And I agree with why we squeeze the last bit out of the hose as well!!

[Monty]

to answer about the gas left in the hose from one person filling up to the next...there's approximately 1 gallon of gas left in the hose after you switch the pump off and hand the hose up. That is 1 gallon of gas you paid for but didn't receive. Now if ppl realized this we might have some outraged ppl out there. Used to you could switch the pump off and drain the hose into your tank to get all the gas you paid for. However once you hung the hose and drove off the gas in the hose would drain back into the underground tank. This only applied to the older gravity fed pumps where the hose is anchored above the pump. Not sure about the newer designs nor the chest high pumps. Only reason I know about this was I worked in a gas station once and the owner used to brag about essentially selling the same gallon of gas over and over and turning a nice profit on a builtin flaw in the pumps. Since I didn't drive (learned to drive at 26 ), it didn't bother me then, now it makes me go hmmmmmm.

 

I find this hard to believe. Take a gas can and pump one gallon into it, then pay for your one gallon. Whatever is left in the hose belongs to the gas station. You pumped a gallon, and paid for a gallon. Simple as that.

[Flyinfool]

I find this hard to believe. Take a gas can and pump one gallon into it, then pay for your one gallon. Whatever is left in the hose belongs to the gas station. You pumped a gallon, and paid for a gallon. Simple as that.

 

Now go home and measure that gallon to see if you actually got 1 gallon or did you leave some of your gallon that you paid for in the hose. All of the gas that is past the meter is yours, this includes the hose and some internal pump plumbing.

 

To me it is not worth the hassle of trying to get a few extra drops of gas out of the hose. Even though those drops are technically and legally mine. I tried it once to see just how much I could squeeze out of the hose after the pump shut off, it was only about 3 oz into a measuring cup or 1400 yards of riding.

[Monty]

Can is marked at one gallon. I make sure, cause I'm mixing it.

[elmicko]

Now go home and measure that gallon to see if you actually got 1 gallon or did you leave some of your gallon that you paid for in the hose. All of the gas that is past the meter is yours, this includes the hose and some internal pump plumbing.

 

To me it is not worth the hassle of trying to get a few extra drops of gas out of the hose. Even though those drops are technically and legally mine. I tried it once to see just how much I could squeeze out of the hose after the pump shut off, it was only about 3 oz into a measuring cup or 1400 yards of riding.

 

And following that same logic, the first few pint or so you put in your car when you turned the pump on actually belonged to that guy who used the pump before you got there, so it all equals out.

[Monty]

[Bobby G]

OK, back to the original question, I think I get it that most of you guys are fine with regular 87 octane gas, but that it's a personal thing and that using 89 or 91 can't hurt the V4, but may not help it either.

 

As for the amount left in the hose, I rarely pump gas where there is a shared hose. I'm strictly a QT or Shell guy, and all of my regular fuel stops have dedicated hoses. But if I can't, then I pretty much fall on the "who cares" side of the issue.

 

Thanks again for the info.

[hig4s]

From page 3-11 of the 07 owners manual

"Your Yamaha engine has been designed to use regular unleaded gasoline with a pump octane number [(R+M)/2] or 86 or higher, or a research octane number of 91 or higher."

 

If you check the pumps you will find they are giving the [(R+M)/2] rating..

 

Also the comment about higher octane burning slower is only sorta of true, in everyday pump gas it is correct, but not in gas in general, racing gas of almost any octane can be designed for faster or slower burn rates depending on application..

 

But for standard everyday pump gas, the lowest octane you can run without pinging (pre-detonation) will be the most efficient and produce the more horse power.

[GaThumper]

to answer about the gas left in the hose from one person filling up to the next...there's approximately 1 gallon of gas left in the hose after you switch the pump off and hand the hose up. That is 1 gallon of gas you paid for but didn't receive. Now if ppl realized this we might have some outraged ppl out there. Used to you could switch the pump off and drain the hose into your tank to get all the gas you paid for. However once you hung the hose and drove off the gas in the hose would drain back into the underground tank. This only applied to the older gravity fed pumps where the hose is anchored above the pump. Not sure about the newer designs nor the chest high pumps. Only reason I know about this was I worked in a gas station once and the owner used to brag about essentially selling the same gallon of gas over and over and turning a nice profit on a builtin flaw in the pumps. Since I didn't drive (learned to drive at 26 ), it didn't bother me then, now it makes me go hmmmmmm.

 

Yep, I used to smile every time I bought gas then flipped the lever off and pulled the handle again to drain that last bit of gas into mmy tank!