Fuel choice
Cruiser
Joined: Oct 2009
Posts: 136
Likes: 0
From: Ohio
Lower octane will cause pinging. The thing with pinging is you can't hear it until it is severe. Yes, you cannot hear mild pinging, although knock sensors can. Sportsters do not have them. Even mild pinging can damage the engine.
The bottom line - better stay away from low octane. If you need to use it do not drive it hard.
Another question is - do I get the fuel I'm paying for? The truth here is there is about 0.5 gal of previous fuel in the hose and pump, in case of common hose. You must be very lucky if someone pumped premium before you. Normally it was regular and with our peanut tank you'll get mixture of 25% regular / 75% premium when pumping 2 gal.
Tip: Look for gas stations that have separate hoses.
The bottom line - better stay away from low octane. If you need to use it do not drive it hard.
Another question is - do I get the fuel I'm paying for? The truth here is there is about 0.5 gal of previous fuel in the hose and pump, in case of common hose. You must be very lucky if someone pumped premium before you. Normally it was regular and with our peanut tank you'll get mixture of 25% regular / 75% premium when pumping 2 gal.
Tip: Look for gas stations that have separate hoses.
Elite HDF Member
Joined: Jul 2010
Posts: 4,828
Likes: 8
With the nozzle being at the end of the hose, and the nozzle controlling shut off, the hose would have to maintain fuel in it. The pump would regulate the amount of fuel pumped, so by theory yes you would lose whatever is in the hose between the nozzle and the regulator, however, when you begin to pump there is already fuel in the hose between the regulator and the nozzle, so technically it would be a wash. To clear it some, you would be paying for the half gallon or so that is in the hose, but would have gotten a free half gallon or so that the previous guy left behind. Obviously though, if the fuel drains back this would not be the case.
As for pinging, high octane is not usually required. most vehicles will do perfectly fine without it. It is only high performance cars, cars that have been custom tuned, or recreational vehicles that tend to run hot that high octane fuel is required. Harleys are air cooled, therefore could benefit from higher octane fuels. You can always run higher octane, just not lower. Ethanol slows the fuel rate which decreases detonation (pinging), but this is also a way that the gas companies rip America off. They are allowed to use inferior, lower octane gasoline because the ethanol brings the rating back where it is rated at. You are paying for inferior gas that burns faster and costs more and more at the pump.
As for pinging, high octane is not usually required. most vehicles will do perfectly fine without it. It is only high performance cars, cars that have been custom tuned, or recreational vehicles that tend to run hot that high octane fuel is required. Harleys are air cooled, therefore could benefit from higher octane fuels. You can always run higher octane, just not lower. Ethanol slows the fuel rate which decreases detonation (pinging), but this is also a way that the gas companies rip America off. They are allowed to use inferior, lower octane gasoline because the ethanol brings the rating back where it is rated at. You are paying for inferior gas that burns faster and costs more and more at the pump.
Elite HDF Member
Joined: Jul 2010
Posts: 4,828
Likes: 8
Incidentally, ethanol fuels are not worse for pinging, actually they are better for it. The alcohol/ethanol fuels will not pre burn like gasolines will, and that is what pinging is (fuel burning before the piston is in it's firing range at TDC plus-minus a few degrees). Pinging is also called pre-ignition, for this reason. Ethanol/alcohol does not destroy an engine by ping. It's damage is in it's corrosiveness. Any gasoline engine by theory can run off of pure ethanol just fine, the reason why engines/vehicles have to be altered to run ethanol or alcohol is because they need harder fuel lines, tank liners, etc., that can handle the corrosive properties of the fuel.
Account Deactivated
Joined: Oct 2009
Posts: 1,757
Likes: 8
From: Central Florida
The .5 gal in the hose,,thats why I run 93 octain and never top off,,
always fill from reserve.
You top off two or three times In a row,,,1 gallon at a time yer octane level Is 90,,Imagine that
An 883 efi or carb may do fine on 87,,
But a 1200 EFI,,,needs 93,,,
You keep putting 87 in a efi1200 and you may,,,just may start
building carbon on the piston top..
Ping hell,,,can you say "I Cracked a Piston"
always fill from reserve.
You top off two or three times In a row,,,1 gallon at a time yer octane level Is 90,,Imagine that
An 883 efi or carb may do fine on 87,,
But a 1200 EFI,,,needs 93,,,
You keep putting 87 in a efi1200 and you may,,,just may start
building carbon on the piston top..
Ping hell,,,can you say "I Cracked a Piston"
Last edited by Osco; Apr 25, 2011 at 01:53 PM.
Account Deactivated
Joined: Oct 2009
Posts: 1,757
Likes: 8
From: Central Florida
Incidentally, ethanol fuels are not worse for pinging, actually they are better for it. The alcohol/ethanol fuels will not pre burn like gasolines will, and that is what pinging is (fuel burning before the piston is in it's firing range at TDC plus-minus a few degrees). Pinging is also called pre-ignition, for this reason. Ethanol/alcohol does not destroy an engine by ping. It's damage is in it's corrosiveness. Any gasoline engine by theory can run off of pure ethanol just fine, the reason why engines/vehicles have to be altered to run ethanol or alcohol is because they need harder fuel lines, tank liners, etc., that can handle the corrosive properties of the fuel.
Account Deactivated
Joined: Oct 2009
Posts: 1,757
Likes: 8
From: Central Florida
Anybody want a real Treat ?
Got a Marina near by ?
If So Grab a 5 gallon can, jump in yer cager an get some
Non ethanol premium fuel off the docks.
Before ya put It In yer tank drain the 10% ethanol into a container,,
Set both about ten feet apart,,
NOW don't be stupid about this,,,,go take a whiff,,,thats a SMALL sniff
of each fuel.
You don't have to stick yer snozola right into the hole just get near it.
The difference In smell will freak you out.
Ethanol sucks.
Oh yeah The Bike will run different,,specially carbes bikes,,,,
Got a Marina near by ?
If So Grab a 5 gallon can, jump in yer cager an get some
Non ethanol premium fuel off the docks.
Before ya put It In yer tank drain the 10% ethanol into a container,,
Set both about ten feet apart,,
NOW don't be stupid about this,,,,go take a whiff,,,thats a SMALL sniff
of each fuel.
You don't have to stick yer snozola right into the hole just get near it.
The difference In smell will freak you out.
Ethanol sucks.
Oh yeah The Bike will run different,,specially carbes bikes,,,,
Elite HDF Member
Joined: Jul 2010
Posts: 4,828
Likes: 8
Anybody want a real Treat ?
Got a Marina near by ?
If So Grab a 5 gallon can, jump in yer cager an get some
Non ethanol premium fuel off the docks.
Before ya put It In yer tank drain the 10% ethanol into a container,,
Set both about ten feet apart,,
NOW don't be stupid about this,,,,go take a whiff,,,thats a SMALL sniff
of each fuel.
You don't have to stick yer snozola right into the hole just get near it.
The difference In smell will freak you out.
Ethanol sucks.
Oh yeah The Bike will run different,,specially carbes bikes,,,,
Got a Marina near by ?
If So Grab a 5 gallon can, jump in yer cager an get some
Non ethanol premium fuel off the docks.
Before ya put It In yer tank drain the 10% ethanol into a container,,
Set both about ten feet apart,,
NOW don't be stupid about this,,,,go take a whiff,,,thats a SMALL sniff
of each fuel.
You don't have to stick yer snozola right into the hole just get near it.
The difference In smell will freak you out.
Ethanol sucks.
Oh yeah The Bike will run different,,specially carbes bikes,,,,
Account Deactivated
Joined: Oct 2009
Posts: 1,757
Likes: 8
From: Central Florida
Dammit Man !!!
I ain't never smelled that stuff,,,cool
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Road Warrior
Joined: Jul 2007
Posts: 1,898
Likes: 67
From: Saint Amant, Acadiana
As for pinging, high octane is not usually required. most vehicles will do perfectly fine without it. It is only high performance cars, cars that have been custom tuned, or recreational vehicles that tend to run hot that high octane fuel is required. Harleys are air cooled, therefore could benefit from higher octane fuels. You can always run higher octane, just not lower. Ethanol slows the fuel rate which decreases detonation (pinging), but this is also a way that the gas companies rip America off. They are allowed to use inferior, lower octane gasoline because the ethanol brings the rating back where it is rated at. You are paying for inferior gas that burns faster and costs more and more at the pump.
Engines are designed to run certain octane of fuel. Think of this as shoe fit. You do not want it big nor small, it has to be just right.
Our Sportster engine is designed for 92, so that's the correct octane for us.
Running lower octane creates ping, which is detonation, an unwanted process. Depending how severe it is it may destroy piston rings, damage pistons and connecting rod bearings.
Running higher octane than designed for your engine is less dangerous, it just burns a little slower, in extreme cases it may burn your exhaust valves, normally you just lose a tiny bit of fuel economy.
