Octane Rating

[BIGGREEK_imp]

Hello all! Quick question.

According to the service manual the cb1100s have a 86+ octane rating. Today was my first fillup and I used 93, didnt have an issue at all. BUT, has anyone experienced a better ride with the 87 instead of the 93?

In my Vulcan 750, it also recommends to use 87, I used to put 93 until I read the manual, next day I used 87. It started better, it ran better, and power was increased (weird right?). Granted, this is a carbureted bike vs. the cb with FI.

Thanks!

 

[Powerdogg55]

If you can get ethanol free "Rec Fuel" 90 octane I would highly recommend it. The CB likes this stuff and so will you.

 

[BIGGREEK_imp]

Unfortunately the only midgrade ethonol free is in Maryland by my work (about an hour away).

 

[the_undecider_imp]

There is more gasoline in one gallon of 87 than 93 octane. That is because they use additives to increase the octane rating. I never run higher octane than specified unless it's my old truck. It's got a little higher compression than stock thanks to 140,000 miles of carbon build up.

Reflashing the computer will advance timing and may require higher octane to prevent predetonation. I reflashed my 2013 Mustang and had various tunes with various octane requirements.

Some cars can tell what octane is being used and adjust parameters accordingly. Advertised power ratings are sometimes based on premium grade fuel. I would assume the ECU on the CB is relatively simple and doesn't adapt in this manner.

 

[BIGGREEK_imp]

Yea I know the cars that require 87 or higher are more lenient to the higher rating, and Im sure the Honda can take the 93 just fine. From what I understand, Honda uses [almost] the same fuel injection system in their vehicles, the PG-MFI. In that case, it could very well adjust via o2 readings, knock sensor adjustments, etc... I was just wondering if anyone had noticed differences between both fuels.

 

[Motogeezer1949_imp]

Don recommends 87 octane after the reflash. I use 90 octane ethanol free a lot. Seems to run crisper, but it's probably psychological.

 

[the_undecider_imp]

Don recommends 87 octane after the reflash. I use 90 octane ethanol free a lot. Seems to run crisper, but it's probably psychological.

That's good to know. I asked about octane in the Guhl reflash thread and didn't get a direct answer. I was just planning to email Don when I got closer to sending my ECU to him.

I wish we could get ethanol free fuel around here. Nobody sells it. Even if I had to drive across town, I'd at least get a couple of gas cans to keep the bikes filled with ethanol free fuel. Last time I was able to buy it locally was 2009.

 

[kDiqq_imp]

You'll want to just call Don or email him early. Usually takes a few days to hear back.

I've tried all grades of gas here and noticed not one bit of difference. I told Don I was running 93 octane so we could advance timing as much as safely possible. When filling up the CB, the difference between regular and premium is less than a dollar over a whole tank. On all the air cooled stuff I've owned I run premium just for the added knock protection (that's all the octane rating represents), but with EFI and the ability to run the bike richer over hotter IATs, I would be willing to admit that my 'added protection' is unneeded on a stock bike. But it's my bike and I do what I want

 

[meowguy_imp]

Quote:I've tried all grades of gas here and noticed not one bit of difference.
I've run only 87 since day one with my '13 and have had no problems with knock whatsoever. The motor pulls beautifully in all gears uphill without a hint of discomfort.

 

[mininsx_imp]

There is more gasoline in one gallon of 87 than 93 octane. That is because they use additives to increase the octane rating. I never run higher octane than specified unless it's my old truck. It's got a little higher compression than stock thanks to 140,000 miles of carbon build up.

Reflashing the computer will advance timing and may require higher octane to prevent predetonation. I reflashed my 2013 Mustang and had various tunes with various octane requirements.

Some cars can tell what octane is being used and adjust parameters accordingly. Advertised power ratings are sometimes based on premium grade fuel. I would assume the ECU on the CB is relatively simple and doesn't adapt in this manner.

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.

 

[rocket_imp]

OK, I'll jump into this one. My ex son-in-law drove fuel trucks for a few years. The local independent gas station owner pays less per gallon if they can take the entire tanker's load. So, if he was delivering regular and couldn't empty the truck, the gas station owner would tell him to just dump the rest in the premium tank. An isolated incident ? Perhaps not. But something to think about when comparing octane ratings. We really don't know what's coming out of that nozzle. I've never felt any difference in fuels for any of my bikes or cars. However.... remember Sunoco 260 ??!! When you're 17 years old that stuff could add untold horsepower to Chevy six cylinder. Or maybe not. Rocket

 

[ClassicVW_imp]

Sunoco 260? Of course it was better. That Sh!t would make my Roadrunner do a wheelie.

 

[Django]

Hm, I wonder why you have this low quality fuel in the US?

Here in Europe, cheapest fuel starts at 95 Octan. There are 2 sorts, one containing 5% or less Ethanol, one containing 10% Ethanol, called E10.

Then there is at least one sort of 98 Octan, some brands offer even more than 100 Octan.

The CB has relatively low compression, 9.something. So it needs not that quality of fuel. However, my BMW K1100 had compression 14 to 1, still ok with 95 Octan, but should not have less.

Most sportcars like Porsche here need 98 octan, to allow full power. They can handle less qualitity, will have less power then.

 

[nhawk7504_imp]

High is more difficult to burn. In a modern engine with electronic timing, there is no need for the high octane, except in a car with more performance. Here in Northeast USA it is now 87 octane in my Ford Focus for .495 EUR per litre.

 

[redbirds_imp]

Hm, I wonder why you have this low quality fuel in the US?

Here in Europe, cheapest fuel starts at 95 Octan. There are 2 sorts, one containing 5% or less Ethanol, one containing 10% Ethanol, called E10.

Then there is at least one sort of 98 Octan, some brands offer even more than 100 Octan.

The CB has relatively low compression, 9.something. So it needs not that quality of fuel. However, my BMW K1100 had compression 14 to 1, still ok with 95 Octan, but should not have less.

Most sportcars like Porsche here need 98 octan, to allow full power. They can handle less qualitity, will have less power then.

My understanding is that a different standard is used for Euro and US octane ratings. I think the Low number octane rating is about the same octane in both places. The real shame is that Ethanol fuel, which has less energy per gallon, is forced on the American public by politicians that either through ignorance or agri-business payoffs mandate it's use. Lucky for me that I have several local dealers that sell the mid grade non Ethanol fuel.

 

[gossman_imp]

Been running ethanol since 2000 in all my vehicles and boat, never an issue. Since nothing I have is a high compression engine, regular works fine. My emergency generator never fails to start even after a year, my chainsaw, lawn mower, even the 200hp Merc jet pump on the boat starts whenever I want them to. Ethenol reduces our dependence on foreign oil, makes money for the farmers, and reduces air pollution. I can't argue with that.

 

[the_undecider_imp]

There is more gasoline in one gallon of 87 than 93 octane. That is because they use additives to increase the octane rating. I never run higher octane than specified unless it's my old truck. It's got a little higher compression than stock thanks to 140,000 miles of carbon build up.

Reflashing the computer will advance timing and may require higher octane to prevent predetonation. I reflashed my 2013 Mustang and had various tunes with various octane requirements.

Some cars can tell what octane is being used and adjust parameters accordingly. Advertised power ratings are sometimes based on premium grade fuel. I would assume the ECU on the CB is relatively simple and doesn't adapt in this manner.

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.
Interesting. I always thought gasoline was gasoline, but additives were used to differentiate octane ratings and different types of detergents based on brand (Chevron Techron for instance).

Can you explain more what different blend stocks are and how that can change octane? How does that differ versus an octane booster additive like what you buy at the parts store?

 

[ClassicVW_imp]

Hm, I wonder why you have this low quality fuel in the US?

Here in Europe, cheapest fuel starts at 95 Octan. There are 2 sorts, one containing 5% or less Ethanol, one containing 10% Ethanol, called E10.

Then there is at least one sort of 98 Octan, some brands offer even more than 100 Octan.

The CB has relatively low compression, 9.something. So it needs not that quality of fuel. However, my BMW K1100 had compression 14 to 1, still ok with 95 Octan, but should not have less.

Most sportcars like Porsche here need 98 octan, to allow full power. They can handle less qualitity, will have less power then.

It's a different standard used in Europe than in Canada and the U.S.
The U.S. octane number will be 4 to 6 numbers less than your number for the exact same fuel.

Europe just uses the RON which is the Research Octane Number, while the U.S. And Canada uses a number which is the sum of the RON and MON ( Motor Octane Number ) divided by two. The RON will always be between 8 and 12 numbers higher than the MON.

 

[DGShannon_imp]

Been running ethanol since 2000 in all my vehicles and boat, never an issue. Since nothing I have is a high compression engine, regular works fine. My emergency generator never fails to start even after a year, my chainsaw, lawn mower, even the 200hp Merc jet pump on the boat starts whenever I want them to. Ethenol reduces our dependence on foreign oil, makes money for the farmers, and reduces air pollution. I can't argue with that.

Oh that hurts the ears of someone like me, who has had motorcycles destroyed by this stuff. Any vintage bike with a fiberglass tank, (such as my Montesa trials bikes), will be delaminated. Bikes with plastic tanks, such as my KTM Superduke, various Ducati, Aprilia, and the Harley XR1200, etc. all suffered damage as their fuel tanks would swell up, no longer fit, crack, etc. Look up info on the damage caused to boat owners with fiberglass fuel tanks. Ethanol is absolutely horrendous stuff that pulls moisture out of the air, and into your fuel, damages older fuel systems, runs hotter, gives less energy per gallon, and on and on and on.

Dig in, and see what Honda, and the other motorcycle manufactures, have to say about the warranty on your bike engine if you put greater than E10 in your bike, yet the EPA continues to try and force it, and would have it by now if not for the anti-ethanol efforts. Even the amount left in the pump hose, at a blender pump, could be enough to damage your bike. One of the EPA's great nuggets of wisdom, in one of the hearings... "We can protect the consumer by making sure that pumps never sell less than 5 gallons of gas, so that any E15, or greater, left in the hose can be diluted." All of your bikes, or small equipment gas cans, hold more than 5 gallons? God bless their ignorance.

Do a little digging, such as on the American Motorcyclist Association (http://www.americanmotorcyclist.com...cknowledges_that_ethanol_damages_engines.aspx) website and you will find tons if info. Total fiasco thrust on the American public by ignorant, but well meaning, politicians and greedy lobbyists. All that before we ever get to what it did to food and feed prices by inflating the cost of corn...

Please, everyone here do your research. In the long run, when every aspect of every vehicle has been designed for it, then ethanol may be a good thing. But, the transition from now until then, can cause millions in damage that the EPA just seems to want to turn a blind eye to, and the motorcycle owner is one of several key places that damage will hit. Beyond E10, and the poop starts hitting the fan.

 

[ClassicVW_imp]

Been running ethanol since 2000 in all my vehicles and boat, never an issue. Since nothing I have is a high compression engine, regular works fine. My emergency generator never fails to start even after a year, my chainsaw, lawn mower, even the 200hp Merc jet pump on the boat starts whenever I want them to. Ethenol reduces our dependence on foreign oil, makes money for the farmers, and reduces air pollution. I can't argue with that.

Ethanol is all about there being an over abundance of corn in the U.S. And there being some senior senators from corn growing states that have the power to ram bad ideas down everyones throats. Period.
It doesn't make any sense from an environmental standpoint either, since it's been proven it takes more energy to produce the same amount of ethanol from corn, as opposed to refining that same amount of gasoline.