Not to question if you are right or wrong, but that sounds backwards to me. Are you saying that if I run 89 octane I would get better gas mileage than I would with the 94?
10% ethyl fuel
- Thread starter just4u
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Not to question if you are right or wrong, but that sounds backwards to me. Are you saying that if I run 89 octane I would get better gas mileage than I would with the 94?
Newer (all "vapor recovery" and "drive a way protected") setups will give you 91/93/87 whatever you order...
Here's how they work...
First customer of the day drives in, slides in his credit card, pulls the handle out, presses octane buttons, and the pumps load up. He squeezes the trigger, reducing system pressure, and they kick on, pumping fuel.
When he finishes and replaces the hose handle, a sensor reads an increase in pressure, and the pumps back off. Most of the systems then wait until the transaction code is processed, and then depressurize the unit & hose clear down to the one way valve (next time, look at the hose. See that metal ring about 2 - 3 feet from where the hose comes out of the housing? That's a combination valve/breakaway.
So, you drive up and order up some 93... there will be a few drops of low grade, but that's it - a few drops, nothing more. Pull up to a newer station today & squeeze the handle - that's exactly how much "previous grade" you'd get from the last customer, just a few drops will dribble out.
Here's how they work...
First customer of the day drives in, slides in his credit card, pulls the handle out, presses octane buttons, and the pumps load up. He squeezes the trigger, reducing system pressure, and they kick on, pumping fuel.
When he finishes and replaces the hose handle, a sensor reads an increase in pressure, and the pumps back off. Most of the systems then wait until the transaction code is processed, and then depressurize the unit & hose clear down to the one way valve (next time, look at the hose. See that metal ring about 2 - 3 feet from where the hose comes out of the housing? That's a combination valve/breakaway.
So, you drive up and order up some 93... there will be a few drops of low grade, but that's it - a few drops, nothing more. Pull up to a newer station today & squeeze the handle - that's exactly how much "previous grade" you'd get from the last customer, just a few drops will dribble out.
johns07gmc
Member
I know that seems confusing but with the higher octane you use more fuel do to how much energy it takes to ignite the fuel, so more octane means more energy needed to ignite the gas in the cylinder hence more fuel dumped into the cylinder to get ignition. If you engine is required to run a higher octane they have been designed to get the most out of the engine by using higher octane fuels. So no using 89 octane will not get better gas milage since most Harley's require 91 octane or higher.
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I disagree here. The injector pulse width measured in nano seconds will only meter so much fuel into the cylinder regardless of octane ratings.
johns07gmc
Member
I think we are both right here Glider
since my truck engine can run E85 (I now have the correct octane rating of 105). The engine in my truck sense's the ethanol and changes the pulse width during compression cycle which makes my truck get less gas mileage. Here are a couple of links if anyone wants to read up on what octane means and if you have a flex fuel vehical that can run on e85.E85 - Wikipedia, the free encyclopedia
Octane rating - Wikipedia, the free encyclopedia
kemo
R.I.P
It seems to me that these alternitive fuels do have higher octanes but most engines arn't built for optimun benitfits. I used to run a Ford truck with duel fuel. Natural gas was my second fuel. Octane of natural gas is over 110 but overall performance and mileage was less than with gasoline. I would think with higher octane there should be higher compression and more ign timing. On the truck there was a ign timing controller called a recurve that would change the timing curve depending on fuel. I think all this ethnol stuff is just to get more money from us. In Canada when we converted from imperial to metric we ended up paying more for a litre than a quart. One imperial gall is equql to 4.54 litres. One U.S. gallon is 3.78 litres. Anything to pull the wool over our eyes.
Fourdogs
Junior Member
My 04 RK..only knows the 10 percent blends..I am in Missouri..but when i went to California was in New Mexico and everyone there says it hard to find 91 plus..so they use 87..and add the stuff that Harley sells..not sure what its called ...but My 04 seems to run fine on the 10 percent 93 octane blend.