What fuel/mix do you use?

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Depends if you think more oil or more fuel is richer. There are good arguements for both.

Gary

yeah i guess more oil could be thought of as richer. i associate richer and leaner with carb conditions where more fuel is richer, more air is leaner. so with mix i automatically think richer=more gas
 
OK, another "ambiguous" bite....:laugh:

Specific gravity of....

40:1 is .863
50:1 is .812

Which one's richer?:greenchainsaw:

sorry man you got me here, i don't know anything about "specific gravity". if i had to take a guess i would say it looks like 50:1 is less dense or heavy due to having more fuel per volume. where as the fuel will be "lighter" than the oil?
 
no disrespect intended and correct me if i'm wrong, but i recently did alot of reading that suggested 40:1 was a leaner mix than 50:1. reason being you have less parts of gas per 1 part of oil than you do at 50:1.

I could be bass ackwards in my terminoligy:monkey:
I'll rephrase it .

''I prefer to run a more diluted mix''
Like others have posted ,I think the 50:1 comes from government standrds.
Just like all the cars with their lean burn settings these days.
 
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I use the "fatter" vs. "leaner" analogy where higher oil concentration = fatter, lower oil concentration = leaner.

Nothing high tech, just easier for me to remember instead of the richer vs. leaner.
 
How I remove ethanol

I have used this method to minimize ethanol % in my 2-cycle mixture for several yrs & never had to replace a single fuel line yet.

Fill up any 5 gallon tank w/ high octane gas plus fuel stabilizer. Let the tank sit, undisturbed for 1 week.

Siphon the gas w/ an electric gas pump, but starting at the "top" part of the tank & gradually work your way down.

Stop at about 1 inch from the bottom, toss the remaining gas or save it for parts cleaning. Reason being gasoline is "non-polar" & ethanol is "polar", they don't stay mixed forever. Given enough time ethanol will precipitate to the bottom.

Worked well for me the last 6-7 yrs. Haven't replaced a gas line yet.


After having to install new fuel lines in my Husky 371 3 times in 3 years because the tygon line shrinks and the mix leaks out of the tank I switched to 110 leaded because it is the only fuel around here that doesn't have governmenthanol. I have used it for 2 years now a haven't had an issue. I mix it a 40:1 with Klotz R50 and have been happy.
 
You were right the first time. Rich vs. lean are terms normally used for fuel to air mix ratio's, not fuel to oil mix ratios. Adding more oil doesnt richen the fuel mix, it just lubricates it.

yeah i'm not disagreeing with that, i just meant i never thought that some could be in our discussion and using the terms differently than me.
 
yeah i'm not disagreeing with that, i just meant i never thought that some could be in our discussion and using the terms differently than me.

Yeah, I always think of rich vs. lean as air/fuel ratio.

Adding a little more or less oil to the "fuel" side should not change the A/F ratio much, since oil is technically a fuel, as well, with some BTU's in it ... my cents. Let the carb sort it out!
 
Yeah, I always think of rich vs. lean as air/fuel ratio.

Adding a little more or less oil to the "fuel" side should not change the A/F ratio much, since oil is technically a fuel, as well, with some BTU's in it ... my cents. Let the carb sort it out!

Yeah we're all pretty much splitting hairs here over terminology moreso than functionality.
But I guess thats that the interweb is for :)

TO the OP, I ballpark somewhere between 35-50:1. I havent seen a huge difference in performance or longevity by being much more precise that that, in any of my 2 stroke machines (sled, dirt bike, waverunner, outboards, saws). Of course, an EFI machine would likely be fussier, but it likely takes care of its own oil ratios.
 
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stihl oiling

I went to the stihl website to get their opinion of oil / fuel mixture ratios and was told that they recommend 50 to 1 "Stihl brand oil" for all their machines-----BUT--- if you want to use a different 2 stroke oil, mobil, marine or whatever, then it needs to be mixed at 25 to 1 because of the lubricants and properties in the Stihl brand oil. The Stihl brand has synthetic properties not found in regular 2 stroke oils.
 

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