93 octane
The first sentence contradicts the second sentence.
While higher octane is slower to ignite (which is what helps eliminate ping), it still explodes just as well as any other octane and is not 'less powerful'.
There are millions of dyno sheets out there to confirm that.
Based on your info, race cars should be looking for the lowest octane. But they don't.
While higher octane is slower to ignite (which is what helps eliminate ping), it still explodes just as well as any other octane and is not 'less powerful'.
There are millions of dyno sheets out there to confirm that.
Based on your info, race cars should be looking for the lowest octane. But they don't.
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
Not because it has less power, either. That wouldn't make sense, would it?
It's slower to ignite, so it won't ping. But it ignites with just as much force (if not more).
The slower ignition allows them to time the motors higher.
Guess what timing the motors higher does? More power!
Higher octane allows you to time your motors for better performance and more power. This is no secret. It's been well known for many years!
Road Master
Joined: Apr 2010
Posts: 824
Likes: 2
From: O'fallon IL
Like most of the others here, i try to run 91/93 whenever possible. I've got stuck running 87/89 in some out-of-the-way places. I notice the difference right away when running a lower octane. When i try to roll on the throttle on an upgrade, especially if the bike is loaded down, i get that unwanted ping. Basically, you just have to baby the throttle until you get some better gas. The E10 situation only makes it worse.
No ****. And they run even higher octane than 93.
Not because it has less power, either. That wouldn't make sense, would it?
It's slower to ignite, so it won't ping. But it ignites with just as much force (if not more).
The slower ignition allows them to time the motors higher.
Guess what timing the motors higher does? More power!
Higher octane allows you to time your motors for better performance and more power. This is no secret. It's been well known for many years!
Not because it has less power, either. That wouldn't make sense, would it?
It's slower to ignite, so it won't ping. But it ignites with just as much force (if not more).
The slower ignition allows them to time the motors higher.
Guess what timing the motors higher does? More power!
Higher octane allows you to time your motors for better performance and more power. This is no secret. It's been well known for many years!
More compression = more fuel introduced = more power.
Outstanding HDF Member
Joined: Dec 2009
Posts: 2,502
Likes: 6
From: Lapeer , Mich
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
It is not the timing that produces the power, it is the compression
Back off the timing until you can run that same motor on low octane without ping.
Then put it on a dyno.
Then re read my post that states: "High octane fuel allows you to advance the timing for more power".
We're talkin' in circles here dude.
BTW: No one claimed running high octane in a stock motor (without changing timing), would produce more power.
We said it would run better with less ping. Never said it would dyno higher.
Try backing off the timing and see what happens to the power. (High compression motor).
Back off the timing until you can run that same motor on low octane without ping.
Then put it on a dyno.
Then re read my post that states: "High octane fuel allows you to advance the timing for more power".
We're talkin' in circles here dude.
BTW: No one claimed running high octane in a stock motor (without changing timing), would produce more power.
We said it would run better with less ping. Never said it would dyno higher.
Back off the timing until you can run that same motor on low octane without ping.
Then put it on a dyno.
Then re read my post that states: "High octane fuel allows you to advance the timing for more power".
We're talkin' in circles here dude.
BTW: No one claimed running high octane in a stock motor (without changing timing), would produce more power.
We said it would run better with less ping. Never said it would dyno higher.
Agreed that we are talking in circles but at least it was an enjoyable, and educating circle. My misunderstanding about the context of your posts. Reading them again, I see where you were rebutting the idea that higher octane would produce less power. You are correct in that it would not produce less, though I have read articles that have indicated so. Here is an article by Rick O'Donnell that discusses this very issue:
Octane
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
I was reminded of something while reading that link.
When it mentioned the timing aspect, I started thinking about the knock retard system in our ecm's.
If our ecm pulls timing because it had sensed some knock, you might not notice any knock at all.
On the same note, if the ecm pulls timing because it sensed knock, wouldn't that timing take away some power? (not that you'd likely notice on a stock bike). Just theorizing here.
Splitting hairs here, I know. But as you already pointed out (and I agree), this is fun to discuss and gainful as well.
When it mentioned the timing aspect, I started thinking about the knock retard system in our ecm's.
If our ecm pulls timing because it had sensed some knock, you might not notice any knock at all.
On the same note, if the ecm pulls timing because it sensed knock, wouldn't that timing take away some power? (not that you'd likely notice on a stock bike). Just theorizing here.
Splitting hairs here, I know. But as you already pointed out (and I agree), this is fun to discuss and gainful as well.
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Elite HDF Member
Joined: Nov 2006
Posts: 3,909
Likes: 6
From: Livingston, Texas
With a 9.2.1 compression ratio engine, 91,92, or 93 will all work.
HD has timing pulled out cause they got the engine cut back on Fuel to meet EPA restrictions.
Were driving something that gits better fuel milage than cagers. But because we might be having
FuN they want to put EPA restrictions on us and some states tax us more for riding a bike.
We need to send a message to the people we voted for and let them know how we feel.
And about the EPA and AKehol n the gas.
Higher price for gas and less milage.
Who's makin the money off this scam.
HD has timing pulled out cause they got the engine cut back on Fuel to meet EPA restrictions.
Were driving something that gits better fuel milage than cagers. But because we might be having
FuN they want to put EPA restrictions on us and some states tax us more for riding a bike.
We need to send a message to the people we voted for and let them know how we feel.
And about the EPA and AKehol n the gas.
Higher price for gas and less milage.
Who's makin the money off this scam.
Elite HDF Member
Joined: Apr 2008
Posts: 3,900
Likes: 4
From: way down upon the Suwannee River
I got caught on a coast to coast trip and all I could get at one stop was 87 octane. ran the whole tank out and didn't notice any differance. I still use 93 unless I can't get it. Like many have said , it don't cost that much. But I don't worry about using regular if I have to.