Author Topic: High, Medium or Low Octane?  (Read 16187 times)

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Offline Duke McDukiedook

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Re: High, Medium or Low Octane?
« Reply #25 on: June 05, 2013, 09:52:40 AM »
I know NOT to use ethanol, but what's the consensus on octane for a 1978 750F Super Sport?

It's FINALLY time to ride here in Saskatchewan!

What measurement method is used on the pumps you frequent?
RON, MON, AKI, or PON?

The owners manual for my 77 CB750F states:
 Use low lead or regular gasoline with a Research Octane Number of 91 or higher, or a Pump Octane Number of 86 or higher.

Higher octane gasoline does not contain any more energy per volume than lower ones.
The high dollar outlay does often lead to placebo effect, though. (I paid more, I must be getting more.)

This is most important to remember ^^.

The only reason you might want to go up a pump rating in octane on a stock engine is if your engine is knocking, that's it.
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Offline Muckinfuss

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Re: High, Medium or Low Octane?
« Reply #26 on: June 05, 2013, 12:10:11 PM »
No matter how unpopular it is, Ethanol is not necessarily a problem.....  If it was there would be dead bikes and cars and trucks everywhere.  Show me where they are stacking all the damaged vehicles?  Plus...it ain't gonna go away!!  And there seems to be more misinformation every day.

I know of guys who built high hp turbo street cars that had them tuned specifically for E85,
because the octane is insanely high. Wonder what they are doing to counteract the alcohol,
which is at fully 85% and not 10%

Some people profess that adding Marvel Mystery oil into your tank will offset the effects.  Marvel is naphtha.  If you don't like the sound of ethanol, why would you think naphtha an improvement?  See what I mean about misinformation.  I don't care what you put in your tanks, but at least put it there with actual information behind your decisions and not someone's VooDoo.

Jump ahead to the hard data and stay away from 'stories';  ie: ethanol  ie: octane ratings

Ethanol Burns slower.  This is the same effect you are looking for with higher octane ratings.  This is why ethanol is the primary component of octane boosters. ie; resistance to knock.

gas with ethanol has an inherent instability that makes it start to deteriorate at about 3 months.  this occurs because of its ability to attract water easier than gasoline alone.

ethanol dissolves the binders in fiberglass resins and renders fiberglass gas tanks unusable.  Ask any boater who had a fiberglass tank and made the mistake.

almost every engine 'treatment/cleaner' is alcohol based.  Many also contain acetone.  Look, I've put some goofy stuff in my tank too.  In 1991 coming back from Sturgis I ran out of gas on the Interstate.  I had exactly one quart of Coleman stove fuel packed.....it went right into my tank and I was able to run in 1st gear only, but I made it to the exit and there was a Shell station.  Beat the heck out of trying to push a 1000lb dresser!...but I wouldn't let it happen again.

It takes 14lbs of air to burn 1 lb of gasoline.  It takes 9 lbs of air to burn 1lb of ethanol.  It takes 7lbs of air for 1 lb of methanol.  Alcohols make more power because you can burn a lot more of it.  If you are losing MPG with 10%...you aren't set up right.  Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.

replace rubber parts with nitril or viton parts....

cold starts are more difficult with ethanol mixes....this is why most cold climate winter states have pumps that still put out non ethanol gasoline during the winter.  Getting harder to find each year.  Even the E85 pumps in those states don't have 85% in them...more like 70% when they brew up their winter grades.

From a Motorcycle perspective one big ISSUE with Ethanol is the hygroscopic properties of Ethanol that will have very adverse effects on FUEL TANKS! Because they not only keep Water content in suspension but absorb water from the atmosphere!! Corrosion is a huge concern with Ethanol sitting in a Motorcycle TANK!  Drain them in the Winter!! or use the products made specifically to deal with the ethanol's adverse effects...Sta-bil, Eagle etc.

I go to pumps that supply non-oxygenated gasoline whenever I find them.  It's 91 octane and recommended for vintage cars and small air cooled engines, motorcycles etc.  Non Oxy has no oxygen enhancers in the fuel. It is harder to refine, and therefore should only be used on seasonally run or small engines. It does not collect moisture, therefore it doesn't cause the corrosion that regular gas can cause over a period of time. Oxygen is corrosive, and so is oxygenated fuel. It can ruin seals and hoses made of rubber. Non oxy also causes the engine to run cooler. There is some debate about whether it causes less, or more pollution. It can leave carbon behind in the burning process. It costs more to refine, therefore, more resources are used to make it. It's a dicey debate.
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Offline Retro Rocket

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Re: High, Medium or Low Octane?
« Reply #27 on: June 05, 2013, 01:29:21 PM »









The only reason you might want to go up a pump rating in octane on a stock engine is if your engine is knocking, that's it.

Thats exactly right   ;)
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Offline desertw0lf

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Re: High, Medium or Low Octane?
« Reply #28 on: June 05, 2013, 01:31:32 PM »
No matter how unpopular it is, Ethanol is not necessarily a problem.....  If it was there would be dead bikes and cars and trucks everywhere.  Show me where they are stacking all the damaged vehicles?  Plus...it ain't gonna go away!!  And there seems to be more misinformation every day.

I know of guys who built high hp turbo street cars that had them tuned specifically for E85,
because the octane is insanely high. Wonder what they are doing to counteract the alcohol,
which is at fully 85% and not 10%

Some people profess that adding Marvel Mystery oil into your tank will offset the effects.  Marvel is naphtha.  If you don't like the sound of ethanol, why would you think naphtha an improvement?  See what I mean about misinformation.  I don't care what you put in your tanks, but at least put it there with actual information behind your decisions and not someone's VooDoo.

Jump ahead to the hard data and stay away from 'stories';  ie: ethanol  ie: octane ratings

Ethanol Burns slower.  This is the same effect you are looking for with higher octane ratings.  This is why ethanol is the primary component of octane boosters. ie; resistance to knock.

gas with ethanol has an inherent instability that makes it start to deteriorate at about 3 months.  this occurs because of its ability to attract water easier than gasoline alone.

ethanol dissolves the binders in fiberglass resins and renders fiberglass gas tanks unusable.  Ask any boater who had a fiberglass tank and made the mistake.

almost every engine 'treatment/cleaner' is alcohol based.  Many also contain acetone.  Look, I've put some goofy stuff in my tank too.  In 1991 coming back from Sturgis I ran out of gas on the Interstate.  I had exactly one quart of Coleman stove fuel packed.....it went right into my tank and I was able to run in 1st gear only, but I made it to the exit and there was a Shell station.  Beat the heck out of trying to push a 1000lb dresser!...but I wouldn't let it happen again.

It takes 14lbs of air to burn 1 lb of gasoline.  It takes 9 lbs of air to burn 1lb of ethanol.  It takes 7lbs of air for 1 lb of methanol.  Alcohols make more power because you can burn a lot more of it.  If you are losing MPG with 10%...you aren't set up right.  Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.

replace rubber parts with nitril or viton parts....

cold starts are more difficult with ethanol mixes....this is why most cold climate winter states have pumps that still put out non ethanol gasoline during the winter.  Getting harder to find each year.  Even the E85 pumps in those states don't have 85% in them...more like 70% when they brew up their winter grades.

From a Motorcycle perspective one big ISSUE with Ethanol is the hygroscopic properties of Ethanol that will have very adverse effects on FUEL TANKS! Because they not only keep Water content in suspension but absorb water from the atmosphere!! Corrosion is a huge concern with Ethanol sitting in a Motorcycle TANK!  Drain them in the Winter!! or use the products made specifically to deal with the ethanol's adverse effects...Sta-bil, Eagle etc.

I go to pumps that supply non-oxygenated gasoline whenever I find them.  It's 91 octane and recommended for vintage cars and small air cooled engines, motorcycles etc.  Non Oxy has no oxygen enhancers in the fuel. It is harder to refine, and therefore should only be used on seasonally run or small engines. It does not collect moisture, therefore it doesn't cause the corrosion that regular gas can cause over a period of time. Oxygen is corrosive, and so is oxygenated fuel. It can ruin seals and hoses made of rubber. Non oxy also causes the engine to run cooler. There is some debate about whether it causes less, or more pollution. It can leave carbon behind in the burning process. It costs more to refine, therefore, more resources are used to make it. It's a dicey debate.

Really? Well, Ford Motor Co seems to disagree with you, and regarding last year's EPA ruling regarding the NEWER, higher % blender pumps and the new regulation that will require minimum 5gal purchases, FMC stated that when it comes around, anyone running higher % blended gas will immediately void their warranty. You seem to not mention that prolonged use of ethanol blended gasoline DOES do damage to motors. It is a well documented fact, not misinformation.

Popular Mechanics even ran a bit on it. http://www.popularmechanics.com/cars/alternative-fuel/biofuels/e15-gasoline-damage-engine

Fuel additives are not run on a constant basis, that is completely different from running blended gasoline all the time. Furthermore additives on TOP of blended gasoline only exacerbate the problems in the long term.

Race motors and road motors are two different animals, and you will NEVER put the miles of a road motor on a race motor without some kind of rebuild in there somewhere. Vehicles set up for Ethanol use stainless steel fuel lines. The ethanol blended gas also eats rubber fuel lines. Your solution of "replace everything with viton, etc" is silly, we shouldn't have to. Ethanol blending was and still is a huge scam pushed by the corn industry. I have family IN that industry, and even they agree. It was never a viable replacement for gasoline in terms of cost and time to produce vs output vs benefits.

Another thing worth noting is that race engines built to run ethanol are just that. BUILT to run ethanol. They are not full of old varnish and deposits and crap that ethanol WILL strip off and set to floating about in the motor looking for somewhere more damaging to lodge themselves and build up. Purpose built race motors don't have this issue. Old iron does.
« Last Edit: June 05, 2013, 01:35:58 PM by desertw0lf »

Offline Retro Rocket

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Re: High, Medium or Low Octane?
« Reply #29 on: June 05, 2013, 01:35:09 PM »
No matter how unpopular it is, Ethanol is not necessarily a problem.....  If it was there would be dead bikes and cars and trucks everywhere.  Show me where they are stacking all the damaged vehicles?  Plus...it ain't gonna go away!!  And there seems to be more misinformation every day.

I know of guys who built high hp turbo street cars that had them tuned specifically for E85,
because the octane is insanely high. Wonder what they are doing to counteract the alcohol,
which is at fully 85% and not 10%

Some people profess that adding Marvel Mystery oil into your tank will offset the effects.  Marvel is naphtha.  If you don't like the sound of ethanol, why would you think naphtha an improvement?  See what I mean about misinformation.  I don't care what you put in your tanks, but at least put it there with actual information behind your decisions and not someone's VooDoo.

Jump ahead to the hard data and stay away from 'stories';  ie: ethanol  ie: octane ratings

Ethanol Burns slower.  This is the same effect you are looking for with higher octane ratings.  This is why ethanol is the primary component of octane boosters. ie; resistance to knock.

gas with ethanol has an inherent instability that makes it start to deteriorate at about 3 months.  this occurs because of its ability to attract water easier than gasoline alone.

ethanol dissolves the binders in fiberglass resins and renders fiberglass gas tanks unusable.  Ask any boater who had a fiberglass tank and made the mistake.

almost every engine 'treatment/cleaner' is alcohol based.  Many also contain acetone.  Look, I've put some goofy stuff in my tank too.  In 1991 coming back from Sturgis I ran out of gas on the Interstate.  I had exactly one quart of Coleman stove fuel packed.....it went right into my tank and I was able to run in 1st gear only, but I made it to the exit and there was a Shell station.  Beat the heck out of trying to push a 1000lb dresser!...but I wouldn't let it happen again.

It takes 14lbs of air to burn 1 lb of gasoline.  It takes 9 lbs of air to burn 1lb of ethanol.  It takes 7lbs of air for 1 lb of methanol.  Alcohols make more power because you can burn a lot more of it.  If you are losing MPG with 10%...you aren't set up right.  Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.

replace rubber parts with nitril or viton parts....

cold starts are more difficult with ethanol mixes....this is why most cold climate winter states have pumps that still put out non ethanol gasoline during the winter.  Getting harder to find each year.  Even the E85 pumps in those states don't have 85% in them...more like 70% when they brew up their winter grades.

From a Motorcycle perspective one big ISSUE with Ethanol is the hygroscopic properties of Ethanol that will have very adverse effects on FUEL TANKS! Because they not only keep Water content in suspension but absorb water from the atmosphere!! Corrosion is a huge concern with Ethanol sitting in a Motorcycle TANK!  Drain them in the Winter!! or use the products made specifically to deal with the ethanol's adverse effects...Sta-bil, Eagle etc.

I go to pumps that supply non-oxygenated gasoline whenever I find them.  It's 91 octane and recommended for vintage cars and small air cooled engines, motorcycles etc.  Non Oxy has no oxygen enhancers in the fuel. It is harder to refine, and therefore should only be used on seasonally run or small engines. It does not collect moisture, therefore it doesn't cause the corrosion that regular gas can cause over a period of time. Oxygen is corrosive, and so is oxygenated fuel. It can ruin seals and hoses made of rubber. Non oxy also causes the engine to run cooler. There is some debate about whether it causes less, or more pollution. It can leave carbon behind in the burning process. It costs more to refine, therefore, more resources are used to make it. It's a dicey debate.

There's plenty of negatives right there...?   It is also less efficient, you use more to do the same amount of miles, and IT DOES DAMAGE ENGINES.....
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
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Offline desertw0lf

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Re: High, Medium or Low Octane?
« Reply #30 on: June 05, 2013, 01:37:11 PM »
No matter how unpopular it is, Ethanol is not necessarily a problem.....  If it was there would be dead bikes and cars and trucks everywhere.  Show me where they are stacking all the damaged vehicles?  Plus...it ain't gonna go away!!  And there seems to be more misinformation every day.

I know of guys who built high hp turbo street cars that had them tuned specifically for E85,
because the octane is insanely high. Wonder what they are doing to counteract the alcohol,
which is at fully 85% and not 10%

Some people profess that adding Marvel Mystery oil into your tank will offset the effects.  Marvel is naphtha.  If you don't like the sound of ethanol, why would you think naphtha an improvement?  See what I mean about misinformation.  I don't care what you put in your tanks, but at least put it there with actual information behind your decisions and not someone's VooDoo.

Jump ahead to the hard data and stay away from 'stories';  ie: ethanol  ie: octane ratings

Ethanol Burns slower.  This is the same effect you are looking for with higher octane ratings.  This is why ethanol is the primary component of octane boosters. ie; resistance to knock.

gas with ethanol has an inherent instability that makes it start to deteriorate at about 3 months.  this occurs because of its ability to attract water easier than gasoline alone.

ethanol dissolves the binders in fiberglass resins and renders fiberglass gas tanks unusable.  Ask any boater who had a fiberglass tank and made the mistake.

almost every engine 'treatment/cleaner' is alcohol based.  Many also contain acetone.  Look, I've put some goofy stuff in my tank too.  In 1991 coming back from Sturgis I ran out of gas on the Interstate.  I had exactly one quart of Coleman stove fuel packed.....it went right into my tank and I was able to run in 1st gear only, but I made it to the exit and there was a Shell station.  Beat the heck out of trying to push a 1000lb dresser!...but I wouldn't let it happen again.

It takes 14lbs of air to burn 1 lb of gasoline.  It takes 9 lbs of air to burn 1lb of ethanol.  It takes 7lbs of air for 1 lb of methanol.  Alcohols make more power because you can burn a lot more of it.  If you are losing MPG with 10%...you aren't set up right.  Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.

replace rubber parts with nitril or viton parts....

cold starts are more difficult with ethanol mixes....this is why most cold climate winter states have pumps that still put out non ethanol gasoline during the winter.  Getting harder to find each year.  Even the E85 pumps in those states don't have 85% in them...more like 70% when they brew up their winter grades.

From a Motorcycle perspective one big ISSUE with Ethanol is the hygroscopic properties of Ethanol that will have very adverse effects on FUEL TANKS! Because they not only keep Water content in suspension but absorb water from the atmosphere!! Corrosion is a huge concern with Ethanol sitting in a Motorcycle TANK!  Drain them in the Winter!! or use the products made specifically to deal with the ethanol's adverse effects...Sta-bil, Eagle etc.

I go to pumps that supply non-oxygenated gasoline whenever I find them.  It's 91 octane and recommended for vintage cars and small air cooled engines, motorcycles etc.  Non Oxy has no oxygen enhancers in the fuel. It is harder to refine, and therefore should only be used on seasonally run or small engines. It does not collect moisture, therefore it doesn't cause the corrosion that regular gas can cause over a period of time. Oxygen is corrosive, and so is oxygenated fuel. It can ruin seals and hoses made of rubber. Non oxy also causes the engine to run cooler. There is some debate about whether it causes less, or more pollution. It can leave carbon behind in the burning process. It costs more to refine, therefore, more resources are used to make it. It's a dicey debate.

There's plenty of negatives right there...?   It is also less efficient, you use more to do the same amount of miles, and IT DOES DAMAGE ENGINES.....

It came off to me like he was saying "it doesn't damage race engines", and that is a strawman argument as race motors are as alike to an old vintage motor that has some miles on it as a steak is to a mickey d's burger.

Offline Retro Rocket

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Re: High, Medium or Low Octane?
« Reply #31 on: June 05, 2013, 02:13:18 PM »
I don't know about the USA but we have signs on our fuel pumps that warn NOT TO USE ethanol fuel in boat engines, the guy that fixes my mowers and other small engines told me not to use it in those either, the service intervals increased dramatically, most small engines now have plastic carbies, ethanol screws them in no time....
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Offline TwoTired

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Re: High, Medium or Low Octane?
« Reply #32 on: June 05, 2013, 04:13:36 PM »
No matter how unpopular it is, Ethanol is not necessarily a problem.....  If it was there would be dead bikes and cars and trucks everywhere. 
Actually, there are.  But, many don't persist in that "dead" state because they are repaired.  I speculate it costs more to repair such a vehicle than any "savings" there would be from the ethanol addition.  But, the very people that mandate it's use, benefit from the taxes on repair parts and the income tax paid by the workers who perform the repair.  Even better, when the owner gets fed up with high repair bills (already paid), they then buy a newer vehicle as replacement with all the taxes and fees and employment boosting side effects that entails, including the sales and excise taxes.

Show me where they are stacking all the damaged vehicles? 
In garages and driveways waiting for repair, and recycle parts yards.   Just use google to see all the otherwise undamaged cars sitting about waiting for love or complete destruction.

And there seems to be more misinformation every day.
I can agree to that.  And a lot of it is from the lobby groups promoting ethanol made from food that could otherwise be used to reduce world wide famine areas and reduce costs to everyone buying groceries in the store.

I know of guys who built high hp turbo street cars that had them tuned specifically for E85,
because the octane is insanely high. Wonder what they are doing to counteract the alcohol,
which is at fully 85% and not 10%
While a rediculous and extraneous strawman, I'll say just this.

They rebuild them frequently or they have addressed each and every ethanol related component that could be damaged by ethanol.  I don't know of any ethanol promoting lobby groups supporting any programs to retrofit vehicles sensitive to ethanol's effects.  "Here Mr. consumer, you have to pay for this poison and you have to pay for the antidote when you eventually find it."

Jump ahead to the hard data and stay away from 'stories';  ie: ethanol  ie: octane ratings

Ethanol Burns slower.  This is the same effect you are looking for with higher octane ratings.  This is why ethanol is the primary component of octane boosters. ie; resistance to knock.

As I have learned, ethanol is harder to ignite (resulting in its high octane number) and it burns cooler, as it has less specific energy content.

gas with ethanol has an inherent instability that makes it start to deteriorate at about 3 months.  this occurs because of its ability to attract water easier than gasoline alone.
Actually it doesn't blend or bond with gasoline, additives are need to help this and they break down in about 3 months, depending on storage conditions, which causes separation even if water or humidity is not present.  Water accelerates the process of separation even faster, like the same day.  In fact, you can remove the ethanol from gas by adding water to it and waiting for the ethanol water bonded mixture to settle to the bottom, then siphon off the top layers of real gasoline.

It takes 14lbs of air to burn 1 lb of gasoline.  It takes 9 lbs of air to burn 1lb of ethanol.  It takes 7lbs of air for 1 lb of methanol.  Alcohols make more power because you can burn a lot more of it.

Whoops, start with some good facts and tie misinformation to it.  Hmmm
Alcohols do NOT make more power.  Engines that have upped the compression ratio or are inlet boosted CAN make more brake horsepower, because of the compression or manifold pressure boost, NOT because of alcohol in place of gasoline.  Both fuels need oxygen to combust.  You get more power when their is more oxygen per unit of volume, which is what boosting and higher C/Rs does.

If you are losing MPG with 10%...you aren't set up right. 
Partially true, guess.  Carbureted engines designed for real gas, certainly won't meter in proper proportion with the poisoned/diluted fuel. However, with the lower energy content of ethanol, you will have to use more of it exert the same force as gasoline.  MPG absolutely MUST suffer regardless of tuning.

Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.
How is it again that using more fuel increases MPG?

replace rubber parts with nitril or viton parts....
Yes, and this expense offsets the consumer savings in blending with ethanol?

From a Motorcycle perspective one big ISSUE with Ethanol is the hygroscopic properties of Ethanol that will have very adverse effects on FUEL TANKS! Because they not only keep Water content in suspension but absorb water from the atmosphere!! Corrosion is a huge concern with Ethanol sitting in a Motorcycle TANK!  Drain them in the Winter!! or use the products made specifically to deal with the ethanol's adverse effects...Sta-bil, Eagle etc.

And yet, you are pro-ethanol?  ???

I go to pumps that supply non-oxygenated gasoline whenever I find them.  It's 91 octane and recommended for vintage cars and small air cooled engines, motorcycles etc.  Non Oxy has no oxygen enhancers in the fuel.  It is harder to refine
Hows that?  They made gasoline for many years before "oxygenation".  How is it harder to make something without adding something "extra"?

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Offline Bailgang

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Re: High, Medium or Low Octane?
« Reply #33 on: June 05, 2013, 07:20:01 PM »
  Alcohols make more power because you can burn a lot more of it.  If you are losing MPG with 10%...you aren't set up right.  Bigger jets. Diddle with the timing.  More fuel to get the same BTU's converted to forward motion.

If I were to run straight alcohol then I'd have to put more alcohol in from the start just to get a motor to put out as much hp as the same engine would on gasoline so right off the bat the fuel mileage takes an absolute dump, high compression piston or not, the air fuel ratios you showed plus the fact that a given amount of alcohol puts out less BTU's than same amount of gas to begin with says it all. If I'm running E10 and losing fuel mileage how is putting larger jets in going to help my MPG? If I have to put more fuel in just to achieve the same BTU then that means my MPG will only be worse than it was before regardless of how I set the timing.

I'm not knocking ethanol, I'm all for getting this country off of foreign oil, I'm just not so sure alcohol of any sorts is the answer.
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Offline Muckinfuss

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Re: High, Medium or Low Octane?
« Reply #34 on: June 06, 2013, 12:40:34 PM »
Too funny......running around with your hair on fire over ethanol beliefs.  Sorry I got you all worked up, but hey, I'll have another shot at it!!   Look, I've been building engines since 1962 and I'll let you in a little secret....until you dyno one with a sniffer....everything stated by you is opinion.  Using words like "I speculate", and such don't make something a fact.   At $1000 per day for a dyno, I doubt there are any receipts other than mine.  Look, this isn't a political fight and by all means, I don't have a dog in the fight as to whether you use E10, E85 or camp fuel.  But there are facts and they seem to be a problem for some.

Fact: Ethanol DOES effect Rubber as it makes it soft over time and that it makes it weak enough to deteriorate with the flow of fuel thus weakening the rubber from the insides, HOWEVER,people been using rubber hoses in stills for over 250 years without complaints. (100% Ethanol)  Perhaps the quality of the rubber is the issue, not the quality of the gasoline.

Fact: E-10 is 90% gasoline and 10% ethanol. The difference in jet size for "optimal performance" between gasoline and E-10 is very little.  Of the 10% that is alcohol you need to go about 30% richer - so 30% of that 10% is only 3% by weight. By volume (jet size is based on volumetric flow) alcohol is heavier than gas per unit of volume by 16% so by weight you are running less than 2% leaner at your jets when running E-10.

Fact: 10% ethanol would be energy of 96.6% of 100% gasoline. So you'd see 3-4% loss in power without any adjustments. (Ethanol BTU @ 67% of gasoline)

Fact: You will never get back 100% of your non-oxygenated MPG, but you can get most of it with correct set up when using a carburetor fed engine.  That includes timing adjustments, not just a jet change.  I thought that was understood by all those who talk the octane game.  You need a dyno to get there because we're talking 3/4 to 1.5 degree advance on these little things, which is too small to guess at with any accuracy.  With an ECU system, all sorts of trick stuff can be accomplished.....All of those steps amount to chasing a five dollar bill with a twenty.

Opinion: IF you are that concerned about MPG on a 40 year old Honda SOHC, maybe it's time to buy something else.....like a 40 year old 125 instead.

Fact: Ethanol, whether run straight or part of a gas ethanol mix, allows for more compression, run straight there is 30% more liquid going into your engine which expands more and has a "latent heat content" which all adds up to more power potential than gasoline. (even though it has less BTU per gallon it pushes hard longer on the piston).

Fact: Ethanol dyno testing done on carburetted V8 engines a few years ago (1984, by me) showed, on average the fuel blends ranging from 6%-8% and Chevron pump gas did not increase HP but did have a wee bit more torque.
 
Fact: Ethanol is NOT corrosive - it is a solvent that will dissolve and carry any corrosion in the fuel system but in a new system (or one that is clean) there are no problems.  Simple high school chemistry.

Fact: Any varnish etc. released from a 'dirty' engine would be carried in a form that would be far less damaging to an engine top end than what get's through a standard K&N air filter.....even a properly oiled one.  91% of the particles that get through a K&N are 40 microns and smaller....they don't get any smaller either.  Varnish and such that are dissolved into the fuel on its way into combustion get reduced to a molecular size and suspended in the atomization.  Not even close to a sandpaper effect as implied.  Opinion here: I'll bet those stories from someone who knew someone that had a carburetor dissolve right before their eyes actually were a little exagerated and maybe the problem was more of too many visits to Autozone to buy 'go faster' gas tank additives on a daily basis.

Fact: Ethanol will also run lean of the "correct" mixture quite happily. Ethanol will not dissolve rubber hoses that are currently sold for fuel systems and will not cause rust in steel lines, brass fittings or Viton needles and seats or o-rings made of Nitril or Viton.

Fact: Too much octane in a vehicle that doesn't need it and you lose throttle response and low end torque (due to the slow burn).  Too little octane and you couldn't run enough timing to make max power.  And so it goes...racers all over the world still hem and haw over which race fuel they should be running. 110 or 112? 114 or 116? 118?   This is no different on your street machine....it's your money.

Fact: Some of us learned through the explosion of driveway hot rods built by shade tree mechanics in the 1950's and 60's that Ethanol is as easy to use as gasoline except where it is atomized in the carb in high horsepower configurations using 100% ethanol and only a carburetor.  There are some real mods that have to be made in the emulsion tube design to make it work well.  It was easier to use the supercharger.  Still is in most cases.  E-10...not worth the effort ($$$) to get back 2-3 of the 3.4% lost.

Fact: The only difference between street engines and race engines is the amount of air that can be stuffed in them.  All engines are an air compressor that has an ignition and fuel thrown at it.  There are production motorcycles with turbos, superchargers, high compression etc.  everything that a race engine has.  Even Nitrous Oxide.  Anyone who tears engines down constantly doesn't know what they are doing with their tools or their money.  They do get torn down, but not because of the fuel used, but because of the strain of such high performance on bearings, rods, and valve train.  Every street bike built since 1910 has a racing heritage from board track to flat track to GP to ....  To somehow claim that a Honda SOHC is so radically different than any other race engine....doesn't make sense.  That's the straw man.

Fact: Ethanol is sold in steel cans at the hardware store. Aluminum is very sensitive to electrolysis and water is very bad for it. Ethanol can carry up to 5% water (rarely happens even in western Washington with all their humidity) which MIGHT affect aluminum....but probably not in an average person's lifetime. 

Fact: Ethanol was used in internal combustion engines prior to Prohibition and once it was repealed, by 1933 it was back being used again as an octane booster.  There was never any engineering uproar.  There was never any chemistry uproar.  Only in the past few years has there been uproar....mostly political and probably feed by Big Oil.  For some.. Marketing = misinformation.  For others Marketing = truth.  In reality...truth = chemistry + math.

The closest thing to a perfect, non-ethanol fuel that I know of is Shell URT Advanced.  It's expensive and hard to find.  You are own your own for that part.

The bottom line is that the difference in power between gasoline and E-10 is so slight that you would have to use precision jets, in half sizes to correct it and the difference in power output is less than you would get between two different days at the track for most applications.  Just as an aside, having been at the track since I was 13 years old running stuffer plate quad carb set ups on my go cart to track racing my Corvette at Mid-Ohio.....every person I've ever known that was a gear head will take performance over MPG every time.  To that end, as more and more alcohol makes its way into our pump fuel....the powers that be will have a very real problem on hand, because E85 creates MORE HP than the gasoline it replaces and mileage goes down 20% or more from the unrealistic MPG expectations because everyone loves the thrill of putting their foot in it!  E85 was track fuel long before it was getting into your neighborhood pumps.  How long even E-10 will be available for vintage engines, I have no idea.  And at what cost is anyone's guess.  Best to bite the bullet and put that Nitril and Viton in now, rather than later.  You know that as soon as it's a must have, it will cost ten times as much.  Even tho I look for non-oxegenated fuels, I'm set up as best I can be for the inevitable. 

And to the guy about boat engines....it's all about the fiberglass gas tanks...not the engines.
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Offline Retro Rocket

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Re: High, Medium or Low Octane?
« Reply #35 on: June 06, 2013, 01:37:48 PM »
Quote
And to the guy about boat engines....it's all about the fiberglass gas tanks...not the engines.

Nothing to do with the tanks at all, I live on the coast and have been into boats all my life, my Dad managed a boat company for over 30 years, we don't use fiberglass gas tanks here,{since 1992} most are stainless steel or plain mild steel or alloy, the warnings are on ALL ethanol pumps, absolutely nothing to do with the tanks. Marine engines here aren't warranted to use ethanol as a fuel, so i am thinking the engine manufacturers probably know a little more than you.... I have read that similar things are happening in the US.

Quote
BP, Shell and Caltex all advise boat owners not to use ethanol mix fuels in boats.

« Last Edit: June 06, 2013, 06:57:52 PM by Retro Rocket »
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Offline 70CB750

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Re: High, Medium or Low Octane?
« Reply #36 on: June 06, 2013, 02:15:14 PM »
I am gonna make some popcorn.

Offline 70CB750

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Re: High, Medium or Low Octane?
« Reply #37 on: June 06, 2013, 03:55:54 PM »
That is not the culture I grew up in.

I mean pop corn, not hot looking girls.

Offline Bailgang

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Re: High, Medium or Low Octane?
« Reply #38 on: June 06, 2013, 06:53:21 PM »
Fact: Too much octane in a vehicle that doesn't need it and you lose throttle response and low end torque (due to the slow burn).  Too little octane and you couldn't run enough timing to make max power.  And so it goes...racers all over the world still hem and haw over which race fuel they should be running. 110 or 112? 114 or 116? 118?   This is no different on your street machine....it's your money.


Are you sure the reason for the lost throttle response and loss of low end TQ was because the race gas was burning too slowly OR was it because it was actually burning too quickly? The next time you ever you use race gas on a stock engine on a dyno and start to see the loss of throttle response an TQ, try retarding the timing and see what happens. Fast burning race gas doesn't need nearly as much ignition advance as pump gas does so if you have the spark coming in too soon then the fuel will literally be burnt up before the piston has had time to take full advantage of it.

Can we agree on the fact that the higher the engine revs the less time it has to burn the fuel in it's cyls?

If so then if a stock engine on a dyno spinning around 6k doesn't have enough time to burn race gas because the fuel is burning so slowly then how in the world would you expect a 500 c.i. NHRA pro stock engine revving at 10k to have time to burn it and make power with it? How about a Formula 1 engine running 96 octane spinning at 18+k rpm? F1 engineers would run as high of octane as they could but the FIA rules mandate 96.

 Are you honestly suggesting that either of those race engines spinning at those rpm's wants its fuel taking its sweet time burning? If so then please explain.

The whole purpose with race gas such as Sunoco Maximal 116 was first off to have an octane high enough to remain stable (key word again is stable) enough to deal with up to 17.1 static comp ratios yet be able to burn fast enough to get a complete burn at high rpm. Some high octane fuels such a 100 octane AV gas do actually burn slower than low octane pump gas but it's high octane isn't the reason why it burns slower. Your typical Lycoming aircraft engine at full throttle is lucky to see 4k rpm even at take off so at that low rpm a fast burning race gas wouldn't be a wise choice. You don't need to be a chemical engineer or have built engines since 62 to realize that gasoline comes in many varieties and formulations and the octane of a given blend is simply a value as to how stable it is, whether it burns fast or slow depends on what it was formulated for and which one you pick depends on the use and purpose of the engine you've put together. That's why as you said "racers all over the world hem and haw over which race fuel to use" and they obviously understood that their choice of fuel was indeed important especially if they are competing in a class where every single HP counts.
« Last Edit: June 06, 2013, 07:11:13 PM by Bailgang »
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Offline Stev-o

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Re: High, Medium or Low Octane?
« Reply #39 on: June 06, 2013, 08:34:27 PM »
Where's Dave with the popcorn!?
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Offline Duke McDukiedook

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Re: High, Medium or Low Octane?
« Reply #40 on: June 06, 2013, 09:26:57 PM »
Quote
That is not the culture I grew up in.

Dude, It was a joke. Girl finds buttered 98.5 degree prize (snake)while sharing the popcorn box sitting on you lap. :)

He means he did not grow up in Uhmerica, not Biblethump, EBF.
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Offline 70CB750

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Re: High, Medium or Low Octane?
« Reply #41 on: June 07, 2013, 03:37:59 AM »
Quote
That is not the culture I grew up in.

Dude, It was a joke. Girl finds buttered 98.5 degree prize (snake)while sharing the popcorn box sitting on you lap. :)

He means he did not grow up in Uhmerica, not Biblethump, EBF.

didn't touch popcorn till I was almost 30; 

same with girls, of course  ;D

Offline Bailgang

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Re: High, Medium or Low Octane?
« Reply #42 on: June 07, 2013, 04:57:12 AM »
Ooops, I better start reading before I run my mouth too. The specific gravity of pump gas can be anywhere between .720 to .770 while race gas can be anywhere between .690 to .796 depending on which one you pick. The specific gravity of a fuel indicates how fast or slow it burns so with #'s like that, assuming race gas means fast burn across the board isn't correct either because some do burn pretty fast while others can be pretty slow and which one you choose depends on your application. I stand corrected. http://www.smithtex.com/racing/fuelcomp.html
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Offline Bankerdanny

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Re: High, Medium or Low Octane?
« Reply #43 on: June 07, 2013, 10:21:00 AM »
Honda Guru Mike Nixon covers this issue in an article on the V4 Honda myths at his excellent website: www.motorcycleproject.com

"10. Finally, for the sake of "cooler running," premium fuel is promoted by some on the Internet. Anyone who has worked around Hondas, or for that matter any of the Big Four brands, for any length of time, knows that their standard road models have been designed to run on unleaded 87 octane for so long that this fact is about to pass into the annuls of history. A Honda bulletin about this exists dated 1971, so we have to look at least that far back. Premium fuel is a bad idea on bikes not specifically designed for it (such as Honda's own Turbo and any number of current hyperbikes). Premium carbons up the valves prematurely and is the cause of much of the top end work that needs to be done on 70s and 80s Hondas, especially Gold Wings and inline fours."
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Offline Muckinfuss

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Re: High, Medium or Low Octane?
« Reply #44 on: June 13, 2013, 10:05:11 AM »
Best non-techy report on the FUD factor surrounding Ethanol from a marine engine manufacturer!!!  FUD=fear, uncertainty, and doubt.

http://www.mercurymarine.com/media/mercury/documents/2011_Fuel_Care_Webinar-2011-08-25_1.pdf
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Offline Bankerdanny

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Re: High, Medium or Low Octane?
« Reply #45 on: June 13, 2013, 10:42:04 AM »
That's a really interesting presentation.

Thanks
"The problem with quotes on the Internet is that you never know if they're true" - Abraham Lincoln

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Offline Hondell

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Re: High, Medium or Low Octane?
« Reply #46 on: June 13, 2013, 11:56:47 AM »
Ethanol in race engines?? I must be missing something. I've always used METHANOL in my drag engines (car and bike). Never seen anyone pouring ethanol into a fuel car (or bike).
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Offline TwoTired

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Re: High, Medium or Low Octane?
« Reply #47 on: June 13, 2013, 12:05:48 PM »
Best non-techy report on the FUD factor surrounding Ethanol from a marine engine manufacturer!!!  FUD=fear, uncertainty, and doubt.

http://www.mercurymarine.com/media/mercury/documents/2011_Fuel_Care_Webinar-2011-08-25_1.pdf

It was interesting, in a pseudo tech marketing way.  But, in the end it was all to promote sales of their own bottles (3 "must haves", no less) of "snake oil".
"Buy these bottles to cure problems foisted upon you by corn lobby groups and government."   Spend even more money!  To US!  We won't tell you what is in it or how it works to achieve those promised goals.  Trust our "BRAND".  It's good for our bank accounts!

I did try to find the MSDS for the 3 products.  But, the hoops required were too great for my limited time.  Can anyone find proper pointers?

Of course they are going to support ethanol.  It creates a good sales opportunity.
Lloyd... (SOHC4 #11 Original Mail List)
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Offline Retro Rocket

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Re: High, Medium or Low Octane?
« Reply #48 on: June 13, 2013, 03:30:57 PM »
Best non-techy report on the FUD factor surrounding Ethanol from a marine engine manufacturer!!!  FUD=fear, uncertainty, and doubt.

http://www.mercurymarine.com/media/mercury/documents/2011_Fuel_Care_Webinar-2011-08-25_1.pdf

You seem to have a hard time either reading or hearing, your government, my government and many others DO NOT ALLOW ETHANOL FUEL FOR USE IN BOAT ENGINES , also here in Australia, THE FUEL COMPANIES BP, Shell and Caltex all advise boat owners not to use ethanol mix fuels in boats. {we have the highest boat ownership rate in the world} You stated most of the problems with ethanol earlier in the thread then refuse to believe that the moisture absorbing, corrosive nature of ethanol is no problem in boat engines. It seems you have a problem understanding exactly what we are saying. I live on the Queensland coast, we have the Great Barrier Reef, some trips to the reef take 12 hours + at sea and the boats stay there for a couple of weeks at a time, plenty of time for your precious ethanol to accumulate moisture in the fuel tanks in boats and corrode or damage fuel lines and rubber seals, the simple fact that there is any risk at all means it SHOULD NEVER BE USED AT SEA AS A FUEL... Do you even start to understand the relevance here..? I have worked at sea on fishing boats that stay out for a week or more at a time and i can tell you that breaking down is the last thing you want.....  Besides, the problems with ethanol are well documented and to use it as a permanent fuel source means that you must do more maintenance to your fuel system to have it work efficiently,{without damage} a small percentage of the population is capable of doing that without costing them money {well less anyway}, so therein lies the problem. Until tanks and fuel systems are made maintenance free to run on ethanol, and it is actually made more efficient,  it is only a taxpayer funded rubbish scheme like plenty of others..... Growing food for fuel, while another subject altogether, is one of the most stupid things humans have ever done, period....  Seriously, you sound very naive.....
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Offline Fritz

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Re: High, Medium or Low Octane?
« Reply #49 on: June 13, 2013, 04:32:33 PM »
Over here we've got the choice between E10, 95 RON or "Super Plus" RON 98 and some other fancy expensive 'fuel saving', 'power enhancing' brands.
With E10 being the cheepest, I've been using it in my 550F for about 12,000 miles on a daily basis now and made the following observations:
- My carbs bowls are very clean - no corrosion so far
- My fuel lines are still soft, no cracks
- The inlet rubbers, which I installed new about 20,000 miles ago, show cracks but are still tight. Don't know if the cracks are the results of ethanol use or bad quality of the rubber.

I've tried the higher octane fuel, which may contain up to 5% of ethanol, once or twice and the motor seems to run a little bit smoother. But this is a marginal effect and might have other causes (difference in weather conditions).
So, E10 might be a bad idea for bikes that aren't ridden very often. For my type of use I do not see any problem. Or in other words: I don't see a benefit in using non-ethanol high octane fuel in my Honda.

But that's just my experience...

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