Premium Gas
Road Master
Joined: Aug 2006
Posts: 1,200
Likes: 1
From: Okeechobee, Fl
If it was about saving money wouldn't we be riding these little scooters that get 100 mpg?
It doesn't take an engineer to know that higher octane needs higher temps/compression to burn, all that is required to understand that is a small amount of reading comprehension, and the effort to actually do the research and reading. Just about every high school chemistry student understands that.
Some bikes need higher octane, any bike that has 9.2 compression or higher needs the higher octane gas, and an engine with a lower compression runs better on lower octane.
What's so hard to understand about that? It's a very easy concept to grasp. The lower the octane, the lower the temp. needed to burn, that equals lower engine temps.
Higher octane will not harm an engine, other than gum it up, but too low of octane will hurt your engine. That is the reason the engineers that designed the motors call for higher octane.
Road Master
Joined: Aug 2006
Posts: 1,200
Likes: 1
From: Okeechobee, Fl
Are we really talking about gas again?
Why not run premium? If your bike is completely empty it MIGHT cost you an extra dollar for premium, and the manual recommends it. If you cant afford that extra dollar you shoulda bought a Honda!
And yes you will get a little better mileage on regular because it burns hotter, but that is exactly why premium is recommended. It's an AIR COOLED bike, and detonation can be a problem, especially in hot climates and low altitudes.
Why not run premium? If your bike is completely empty it MIGHT cost you an extra dollar for premium, and the manual recommends it. If you cant afford that extra dollar you shoulda bought a Honda!
And yes you will get a little better mileage on regular because it burns hotter, but that is exactly why premium is recommended. It's an AIR COOLED bike, and detonation can be a problem, especially in hot climates and low altitudes.
Use the lowest octane rating you can without pinging. The higher the octane, the hotter the fire, higher the combustion needed to burn it. Most bikes using higher octane do not run hot enough to burn all the gas in the combustion chamber, that means some of the gas you paid for is dripping out of the exhaust pipes and that equals lower gas milage.
Ya know Snarly, you run what you want in your bike and I'll run what I want in mine. It's just that every time this subject comes up and anyone says that they use a lower octane some on here make this assumptive jump that it's about saving money.
If it was about saving money wouldn't we be riding these little scooters that get 100 mpg?
It doesn't take an engineer to know that higher octane needs higher temps/compression to burn, all that is required to understand that is a small amount of reading comprehension, and the effort to actually do the research and reading. Just about every high school chemistry student understands that.
Some bikes need higher octane, any bike that has 9.2 compression or higher needs the higher octane gas, and an engine with a lower compression runs better on lower octane.
What's so hard to understand about that? It's a very easy concept to grasp. The lower the octane, the lower the temp. needed to burn, that equals lower engine temps.
Higher octane will not harm an engine, other than gum it up, but too low of octane will hurt your engine. That is the reason the engineers that designed the motors call for higher octane.
If it was about saving money wouldn't we be riding these little scooters that get 100 mpg?
It doesn't take an engineer to know that higher octane needs higher temps/compression to burn, all that is required to understand that is a small amount of reading comprehension, and the effort to actually do the research and reading. Just about every high school chemistry student understands that.
Some bikes need higher octane, any bike that has 9.2 compression or higher needs the higher octane gas, and an engine with a lower compression runs better on lower octane.
What's so hard to understand about that? It's a very easy concept to grasp. The lower the octane, the lower the temp. needed to burn, that equals lower engine temps.
Higher octane will not harm an engine, other than gum it up, but too low of octane will hurt your engine. That is the reason the engineers that designed the motors call for higher octane.
First of all for the record, Dave posted the first response under my name because I did not log out the last time I used his computer.
Second off, if you have gas coming out of your tail pipe your running your carb too rich and your going to get back fire. You can fix that by leaning it out a bit, and then you should get better gas mileage again. If you have feul injection, you should never have gas coming out of your tail pipe.
Third, I have NEVER heard of higher octane gumming up an engine.
But then again, I don't care about this subject enough to do all the research on it. JMHO I run regular in my V6 and premium in my V-Twin.
Stellar HDF Member
Joined: May 2007
Posts: 3,164
Likes: 6
From: Greenfield, Massachusetts
Call me a fool, but I run premium in my bike (2008) because the manual and my mechanic says to and I run regular in my car (2006) and my pickup (1997) because the manual and my mechanic said so. And BECAUSE of the price of gas, I'm glad it's that way and not the other way around.
Seasoned HDF Member
Joined: Sep 2008
Posts: 46,845
Likes: 22,534
From: Land of the Free, Home of Jack Daniel's
WoW, I don't know what to do after all of that? Shucks, think I'll ride 1 county over and pick up some white lighting and see how that runs in the 'ol scoot.
Seasoned HDF Member
Joined: Dec 2004
Posts: 11,068
Likes: 1,477
From: Texas! Ya mean there's someplace else?
Running too high an octane will cause deposits to build up, especially in the combustion chamber. All else equal, a given amount of a higher octane gasoline will take longer to burn then a lower octane. If the timing is set so that the higher octane fuel isn't completely combusted, then deposits form from the unburned fuel.
Last edited by pococj; Nov 3, 2008 at 06:57 PM. Reason: Forgot to "snip."
Road Master
Joined: Mar 2007
Posts: 1,003
Likes: 0
From: Ada, Michigan
normally run premium however runs fine with 89 octane
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Tourer
Joined: Jan 2006
Posts: 400
Likes: 0
From: Mckinney texas
To each their own but I have run unlead 87 octane since day one.I have an 05 heritage with 87,000 miles on it .The motor runs cool and the spark plugs and clean.Why spend more money on gas? Just cause the book says too?
