Octane question

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I have not read the entire thread in detail, but in skimming I was surprised to find so much confusion, and I think most people missed a key point.

If you read the Echo manual, and I'm sure Stihl is the same, they state the fuel they recommend is 89 octane R+M/2 gasoline. That R+M/2 I think is what is tripping so many people up. That is ROM, the European octane standard. It is a different standard of octane than what north America uses. 89 octane ROM is low quality gas. For comparison, 91 octane ROM is about equivalent to our 87 octane usa standard. Our normal 87 octane gas you get anywhere in the USA exceeds Echo's octane recommendation.

While you definitely want a non-oxygenated gas, it's not worth worrying about anything else for normal saws. Octane is not directly related to how fast a fuel burns, it is nothing but a fuels resistance to pre-detonation. Nobody in their right mind is running racing gas in a normal chainsaw. Any normal pump gasoline 87 to 100 octane is going to perform just fine.
 
Actually, no. The lead oxides are not absorbed into the blood stream. Most of the lead in people was absorbed through the stomach.
"Lead salts are absorbed via the intestine and inhalation. Sources are glazes, paints, additives in leaded fuel, lead pipes, and occupational exposure. Mainly due to the ban of leaded fuel, average lead levels in blood have substantially declined to concentrations below 10 or even 5 μg/dL during the past two decades."
Lead Oxide - an overview | ScienceDirect Topicshttps://www.sciencedirect.com › topics › lead-oxide

There's a whole lot of info out there saying lead oxides are absorbed through the lungs.
 
Actually, no. The lead oxides are not absorbed into the blood stream. Most of the lead in people was absorbed through the stomach.
You are totally incorrect.
In addition after leaded fuel has been ran through a two stroke you are exposed to both lead oxides via combusted lead and organic lead via unburnt HC.
It's mystery to me where some of you guys get these ridiculous conclusions from.
 
I have not read the entire thread in detail, but in skimming I was surprised to find so much confusion, and I think most people missed a key point.

If you read the Echo manual, and I'm sure Stihl is the same, they state the fuel they recommend is 89 octane R+M/2 gasoline. That R+M/2 I think is what is tripping so many people up. That is ROM, the European octane standard. It is a different standard of octane than what north America uses. 89 octane ROM is low quality gas. For comparison, 91 octane ROM is about equivalent to our 87 octane usa standard. Our normal 87 octane gas you get anywhere in the USA exceeds Echo's octane recommendation.

While you definitely want a non-oxygenated gas, it's not worth worrying about anything else for normal saws. Octane is not directly related to how fast a fuel burns, it is nothing but a fuels resistance to pre-detonation. Nobody in their right mind is running racing gas in a normal chainsaw. Any normal pump gasoline 87 to 100 octane is going to perform just fine.
Oh, look! A response that clears up confusion! Make sure you completely ignore it, folks!


*I will say: I like the back and forth. I'm learning a fair amount, even if I feel I'll have to go back and check the info myself for accuracy.*
 
You are totally incorrect.
In addition after leaded fuel has been ran through a two stroke you are exposed to both lead oxides via combusted lead and organic lead via unburnt HC.
It's mystery to me where some of you guys get these ridiculous conclusions from.
I have some here and actually not wanting to use it! I have a few times and I can tell you it burns they hell out of my eyes for one.
 
So is it unwise or safe to use Avgas LL or what?
I have no idea. Not something I've studied. I would say that the lead content is not an issue for personal health.
BTW, lead in fuel is an environmental disaster. It washes into the waterway where there are microbes that can convert the lead oxide into organic lead compounds which can work their way up the food chain.
 
You are totally incorrect.
In addition after leaded fuel has been ran through a two stroke you are exposed to both lead oxides via combusted lead and organic lead via unburnt HC.
It's mystery to me where some of you guys get these ridiculous conclusions from.
Well, there are several papers by ATDSR that address the issue. In particular most of the lead load in American children is sourced from old paint. (Or was, I haven't kept up... as the amount of exposed lead-based paint declines over time, I would expect the contribution to decline.
Note, I am not saying that lead exposure is innocuous. But the path to absorption by humans is more complicated and most of it takes place through the food chain.
 
I have some here and actually not wanting to use it! I have a few times and I can tell you it burns they hell out of my eyes for one.
IMHO it smells much better than pump gas.

From working in an organic lab I can identify many solvents by smell. Usually because some a hole was not working in the fume hoods...
 

Latest posts

Back
Top