lets talk octane!

I have decided my neck of the woods here in iowa sucks in terms of gasoline options. I am having a difficult time finding gas above 87 octane and if i do it has ethanol in it. My baby doesn't seem to be such a fan of the low octane regular unleaded. Of course I am doing my darnedest to get higher octane unleaded, but barring that find should i look into some octane booster? or maybe the high octane race fuel that a gas station in town sells? Should i date kayla or haley? You folks seem to have answers to everything so i threw that last one in just 'cuz :wink:

 

Becarefull with octane boost's as they are meant in most cases to treat a tank of fuel for a car not a bike, A full bottle may be a little over kill.... Date Haley on odd days and kayla on even unless they know each other in which case, date Haley for a month and if it's not going well call Kayla and tell her you made a huge mistake but you see now that she's the one you should be with!!! :wink:
Shaun

 

Hi, Don't want to upset you, but regular unleaded petrol (Gasoline) in the UK is 95 RON!

Maybe I could export it to the U.S. .........?

 

I have found a station near to me that sells pure gasoline, with ~zero~ ethanol in it. That is all I use in my bikes and my truck.

Ethanol has ruined more carburetors, tanks and fuel systems than most people realize. If it were not subsidized by the government it would never have happened.

 

You should read up on what the octane rating means and see if it applies to your situation. The only way a higher than recommended octane will (should?) make any difference is if your bike is currently experiencing detonation (pinging / pre-ignition). Octane is added to increase a fuels resistance to the above mentioned phenomenon. Higher compression than stock, or an altered timing can warrant needing a higher rated gas.

What do you mean by this? Can you give a few more details?

 

most octane boosters at the store are meant for ~20 gallons of fuel. you should look at finding an even mix to throw into your tank. see if that helps.
if all else fails, get a 50 gallon tank in your truck and drive to the nearest 91 octane town and fill up
oh, haley, btw.

 

If I run straight Regular at the point where I'm running this 750 Maxim ... I get a little bit of Knock.
Since the Pistons and Combustion Chamber is Aluminum; I quit using the Regular and use High Test.

The Bike can't possibly run any better than she is right now.
I know I might be wasting 12-Cents a Gallon.
I'm cool with that.
High-test is the way I roll.
It's one of the things I do that don't make sense to anybody else but me.

 

can you explain high test?

 

I, like Rick, routinely run Premium unleaded and mix it with 100 Octane LL Avgas when I have it (which is fairly often, given my profession). Premium is the way to go. You might find a good supplier and stock up by filling a 55 gallon drum of the stuff with a hand pump; it would likely last a year or two, although I'd be leery of storing auto pump gas more than 90 days, even with Sta-Bil in it. Figure out a 90 day supply quantity and buy in bulk. Just my .02......

 

I'm surprised with the 87 octane fuel. That seems very low. Regular unleaded petrol here, is 91 octane, and there are premium 94 and 98 octane fuels available, for about 10- 15 cents more per litre. My XJ likes the 91 octane. A few places have 10% ethanol, but it hasn't made many big inroads yet. We also call a particular fuel called "gas", but that is what it literally is. I run my work ute on it - which has a converted engine. It is Liquid Petroleum Gas, or Propane, which is supposed to be about 100 octane. LPG or Propane for vehicles is about 45c per litre. Unleaded is $1.20 a litre.

How low would the compression on an engine have to be to run 87 octane?

 

Premium usually is 93 octane around here. I've ALWAYS run Premium in whatever bike I'm riding. My Harley DEMANDED it.

 

In North America we use the Pump Octane Number. In the rest of the world you use the Research Octane Number. PON is roughly RON - 5. In otherwords what you call 91 would be 86 here.


XJs call for 91 RON. That's why we can run 87 octane in North America.

 

what all you that aren't from US, Canada and a few other countries have to remember is that we use AKI octane rating on our pumps, not RON.
Our octane rating is based off off (RON + MON)/2 and is therefore ~4 points lower than RON rating.

more to be found at http://en.wikipedia.org/wiki/Octane_rating

 

we have 95 98 and shell v-power i think it is 99octaine.
wonder if the ignition is low in the bike so it can run 87octaine that som countrys have ?

 

Ahh i get it... I recal reading some archived review of 750 Secas from when they were first coming out and the author mentioned the bike should run 91 octane, but looking back the article may not have been from north america. Regardless, the bike will run with 87 in it, but i would like to bump it up if possible. Sadly, NOBODY in the des moines area has higher than 87 unleaded. Ethanol is being shoved down our collective throat.

Related story, i called a gas station in my town to ask what the octane on their regular unleaded was and the kid on the phone didn't know. (Expected this.) I told him to go look at the pumps as there should be a yellow sticker with an octane number on it and he said they don't have it. At which point i asked, "So you don't sell gas with octane ratings?" His reply, "Nope."
:roll:

 

Methanol in high consintrations can damage the seals in these carburetors.

Octane Boost can be added in 5% or less concentrations.

I have use North American's 108 Octane Boost in the past which is 12 oz. per 22 gal. It contains Methanol and T-Butyl Alcohol.

That would equate to 0.55 oz. Boost / per gal of regular gas.
They recommend adding it to the tank first and then adding fuel the throughly mix the Boost into the fuel.

 

alcohol is bad gentlemen.... avoid it if possible.

 

There is a move afoot to REQUIRE 15% ethanol in all non-aviation gasoline in the states. I don't think you're going to have an option much longer.

 

oh man..

 

alcohol isnt bad, its just a different animal and you need to prepare for it....its coming!

i will say this, alcohol requires much more fuel to achieve stoich......so there goes any fuel economy you had. when they switched from MTBE to 10% ethanol my mustangs mileage TANKED!

adding more alcohol to my fuel is fine by me....if they lower the price!

alcohol also runs much cooler and increases the knock resistance, so running 87octane with 10% ethanol should be FINE in one of these bikes.

i was able to run the 87 alky fuel in a 12.5:1 compression race engine (with much more aggressive timing than our bikes) with no pinging. if you cant run it in one of these bikes, you are probably too lean.

 

I wonder.... Why is alcohol bad for our carb seals and if its bad for the carb how about our intake boots? Is it because the alcohol dries out rubber? If so why not add a couple of oz. of marval mystery oil to your alcohol / gas. I add a couple of oz. to my tank every 5 or 6 tanks or so. It can't hurt. I have also noticed that I loose about 10mi per gal. by running 87 instead of 91 oct. Has anyone else seen this dramatic of a fuel milage drop by running the 87?

 

Absolutely! I've put 87 in a few times when 93 wasn't available and I definitely noticed a drop in mpg.

 

Agreed. I run premium in my bike beacuse it saves me more money in the long run. Only a buck or two, but a buck or two is almost a gallon of gas! Thats 3 - 4 times back and forth to work! But if I gotta start putting additives in the gas here soon anyway cause of ethanol, then i'll just switch to 87 along with the additives. Fuel stabalizers or somethin. Driving is getting more and more expensive everyday. Almost a luxury
-Chris

 

I know for sure that on the carbs I've torn down or rejetted, those run on Premium were always much cleaner as well. In fact on one Savage I had the dealer tear down, the mechanic even mentioned to me that I must use Premium. LOL I even run Premium in the Rebels I buy and sell.

 

Alcohol may be "coming" (or should I say, forced upon us). Fine, just get ready to spend more money and more time maintaining any vehicles or equipment that use it. It is not the panacea so many have been whining about.

 

Anyone know WHY they're doing it?? Just cause?? Or to cut back on gas usage?? How many of those politions actually do their own work on the vehicles?? They dont care about us... rar..
-Chris

 

Because they can?!

Seriously though i believe it's supposed to reduce some portion of emissions.

And if it was really that great why would the government have to force it on us?

 

I found this on the internet-

Buna-N rubber is a synthetic rubber originally developed in Germany in the '30s. Buna-N is oil resistant which is why it is a common material used for O-rings. It also stands up extremely well against petroleum products, including good old-fashioned gasoline, which made it an excellent material for accelerator pumps prior to the addition of ethanol-which causes deterioration

Viton is a registered trademark of DuPont and the name of a newer type of synthetic rubber. Unlike Buna-N, Viton is impervious to alcohol as well as to moisture and solvents. David said that Standard has tested Viton to 15-percent alcohol exposure, but they believe that it could be exposed to higher amounts without showing any damage-but those tests haven't been done yet. For the moment, Viton (or other brands identified as ethanol-compatible or non-corrosive) is the best solution to the problem of accelerator pump failure.

http://www.rodandcustommagazine.com/tec ... index.html

 

Two powerful lobbies:

1 - Environmentalists.

2 - Corn growers.

 

mtbe caused more cancer and hurt more of the environment than ethanol does, so here we are!

viton is ok, its the plastic floats that get wasted by the alky.

someone suggested MMO, i would stay away from that snake oil. nothing mysterious about it, and it is worse for rubber than the alcohol! instead i would run a small amount of 2-stroke oil.

this is a table for diesel fuel additives, so most of it doesnt apply to us. it does include MMO and 2 stroke oil. the HFFR test results for lubricity would shock most people. http://www.superdutydiesel.com/forums/a ... 1189097548

 

ingredients of MMO:
dichlorobenzene
naptha
Mineral Spirits
Chlorinated Hydrocarbons (brake cleaner)

 

someone suggested MMO, i would stay away from that snake oil. nothing mysterious about it, and it is worse for rubber than the alcohol! instead i would run a small amount of 2-stroke oil.


Thanks I didn't know that MMO was bad for rubber seals. I won't be trying that styff anymore.

 

It amazes me what a bad rap petroleum has gotten lately thanks to the lobbying and brainwashing of powerful interest groups that are basically, anti American.

It comes out of the freakin' ground for cryin' out loud. Places on the ocean floor it is oozing out of the bottom and methane ("natural gas") is bubbling up all over the planet.

We should be using this fantastic commodity provided to us by mother nature, not trashing it. Using modern technology for top efficiency and clean burning *is* the way to go, but with all the ignorant statements and misleading propaganda out there the average person has been brainwashed into forking over money for pie in the sky "global warming" schemes.

I hope its not too late to save this nation from ending up like cuba.

 

The house I grew up in had the well in an underground room off the basement. House blew up twice before dad found out where it was coming from and routed the well vent outside.

Turns out that when you watered the lawn the water rising and falling in the well would push the gas into the basement. Once enough got to the pilot light in the water heater BOOM!

 

My experience with ethanol has been nothing but positive, i live in melbourne australia, and it is available here in a 10% component. i used it as soon as it came out in my old honda civic, and the car ran better, more evenly, and despite all the negative press, and frequent under the bonnet checking, i found not a single compnent to be corroded, from O rings to fuel hoses, not a thing was amiss.

I have also run my xj650 on 98 octane with no probs, runs great but! nowadays i run 95 due to cost, availability, and mileage. I do believe i can feel the difference between 91 and 95.

concerning the greenies and environmentalists....despite their arguments, they are trying to save us from future monopolies created by shortage of stock, or oil. if we start using alternatives now, we might not be paying $9 a litre for petrol as soon as we would without changing any thing. I think it is ironic that americans are threatened by alternative supplies of energy when the american governments have always insisted foriegn countries deregulate their economies to allow competition.

competition is good, either electronics or cars. so why such a big storm over competition in the world of fuel?

also, i believe south america have been adding ethanol to their fuel in high concentrations for years now, with no adverse effects. not 100% sure of this though.

cheers

 

i dont know what magazine you are reading, but alternative energy sources have been quite a big deal for the past several years in my USA. dont let your opinion be biased based on the jerk-offs that find their way to the front page or the big screen.

here in new england we have oxygenated fuel in the winter, is that just us or do other regions run that as well? the oxygen and ethanol throws the jetting off enough to require a large jump in jets to make things run right again. when they started changing fuel in the winter, i rejetted several sleds for people who suddenly couldnt figure out why it was running like crap.l

 

Competition is where suppliers can sell any product they like, with the features they want and the consumers vote for the best one with their money. That's why we can buy DVD players in the states for under $50 as opposed to north of $1000 a video tape player went for when consumer playback devices were introduced. There is very little regulation of electronics in the U.S.

In the case of petroleum though it's heavily regulated and heavily taxed. Ethanol is subsidized by tax dollars in the field (crop subsidies), and tax dollars after it's produced (50 cents/gallon of tax dollars paid to the ethanol producer). Still, consumers aren't buying as much of it as the government wants so they're working on mandating 15% ethanol content in motor fuel.

Meanwhile, people in Latin America are having trouble affording tortillas (a staple food there) because corn is prohibitively expensive because special interests in the U.S. are trying to force the use of corn as a fuel feedstock.

It's not competition when the government deliberately tilts the playing field with taxes, subsidies and mandates.

I've never had a problem with ethanol blended gasoline and I don't care if the corner service station offers it in whatever blends the proprietor likes. I do object to forcing ethanol on anyone, especially those with older machines or marine engines that are getting hosed in the process.

 

Amen!

 

Exactly. I'm happy that you like ethanol so much (mix Jim Beam into your gasoline if you like) but if you leave that concoction in your equipment for too long a time it turns rancid and will produce obnoxious chemical reactions that will damage fuel systems (i.e. your Yamaha) and you *will* pay the price. There is no pie in the sky despite what some politicians (that will remain nameless) promise.

 

flax is the way to go, soon the world will see.

 

High test? My baby looooves the cheap stuff. Doesn't run as good on the better stuff. No surprise considering what she's expecting...

 

Most regular I see is 87 octane.

 

Right. 87 PON (Pump Octane Number). If you look at the tag it says 91 Research Ocatane (RON) . PON is a tougher standard. 87 PON is roughly 92 RON.

 

You will notice on that decal that these bikes ARE built to run leaded fuel. If you don't add some lead substitute every once and a while your valves aren't getting the lubrication they need to last their full life. You are also wearing out your exhaust valve seats prematurley. I have almost 41K miles on my xj650j and have been runnin lead sub. since I got the bike at 25K mi.. It runns just as stong as the day I got it. I know that on the older heads from leaded days (v-8 chevys and fords) they needed the lead because they don't have hardened exhaust valve seats or hardened valve guides. If these xj's do than the nolead gas is ok.

 

Whats a good Lead additive to use then? Well oiled machines run better <---FACT
-Chris

 

I would check with your local auto parts store. They will have a lead substitute, you can't buy actual lead additive anymore. If you have a gas station that sells the 110 oct race gas that has lead in it also, but it costs $6 a gal. I try to use it every 3 to 4 tanks but its more like every 6 or 7 now.

 

if you arent using it constantly i wouldnt bother. also, the manufacturers knew that lead was being deleted for a LONG time, and the engines were designed accordingly.

no lead=no problem.

 

so your saying that the exhaust seats in our early 80's xj's are hardened?

 

i don't KNOW, but i would be SHOCKED if they weren't. we run mid 70's atv's on unleaded with no issues....late 70's American autos were unleaded prepared, why would our 80's bikes NOT be able to run unleaded?

 

If anyone is still "out there" allow me to complicate the situation. This topic is important to me because I live at 8,000 feet elevation, just bought a 1981 XJ750, and am spending hundreds of dollars getting the carbs rebuilt, resynched, etc. the whole nine yards. This yammy dealer has a great reputation for carb work, but also very slow.

So I want to get the fuel right.

At elevation, the octane is 83 or 85 (I forgot!). Soo, I guess my question is, will I HURT anything or foul anything with premium fuel here?

Thx.