Zeda 100 "Max"

[Nickt919]

Isnt a 20:1 pertty lean on the mixture. You have double the oil of a 40:1.

Am I looking at this wrong or misinterpreting the meaning?
A 20:1 mix is an awful lot of oil.

20:1 is 20 parts gasoline to 1 part oil…
40:1 is 40 parts gasoline to 1 part oil.

So 20:1 should be twice as much oil or half as much gasoline as a 40:1 mix and twice as rich…

I was always told the oil lubricates AND removes heat.
I run the Dominator at 40:1 and still get a decent drip out the pipe end.
I love that oil.

 

[Nickt919]

Is this "new Math" coming back again???...lol...lol.

20:1 mix is 6.4 ounces of oil...40:1 mix is 3.2 ounces of oil...Where do you get that 20:1 is leaner on oil than 40:1???...lol....You have double the oil at 20:1...NOT at 40:1...lol.

I always have to rationalize the oil ratio in simple terms as I posted above or my feeble brain will get it bassakwards

 

[DAMIEN1307]

I was always told the oil lubricates AND removes heat.
I run the Dominator at 40:1 and still get a decent drip out the pipe end.
I love that oil.

Very true...And with the P-85s, They do not drip out of the pipe at all, even at 20:1 during the normal break-in, I have never had so much as one drop...Thats why I am not changing the ratio with mine, no reason to cut back on oil protection...lol.

 

[Chainlube]

These little engine are no more than vintage type engines, and a little more oil isn't going to hurt them at all. All the vintage outboards, sleds and dirt bikes run 25:1, and back then they said good quality SAE 30W.

 

[Cannonball3]

Is this "new Math" coming back again???...lol...lol.

20:1 mix is 6.4 ounces of oil...40:1 mix is 3.2 ounces of oil...Where do you get that 20:1 is leaner on oil than 40:1???...lol....You have double the oil at 20:1...NOT at 40:1...lol.

Guess I didnt specify clearly which mixture. There is less gasoline in a higher(lower#) mix. This may or may not make a substantial difference in most cases and in certain instances more oil might be a good idea.. However in a well tuned build with a carefully jetted carb its noticeable. It will usually affect low to mid range, especially with carbs with a low speed circuit/pilot jet.
My Athena Mina is closely jetted. I have lowered the pilot # to an optimum mixture for clean running and good response.
Drops in temps will greatly affect it, as its jetted in the 70-80s. Gets hotter the mixture richens, colder it leans.
Where I live we have large swings almost weekly. I discovered that a 40:1 mix(normal is 50:1) leaned it just enough for
it to run as normal at reasonably lower temps. I use 40:1 in the colder months, 50:1 in the hotter months.

Also ratios are for oil poured into a gallon of gas. If one has a marked true gallon container and pours the oil in first then fills to a gallon mark, the mixture is leaner still. In your case you would have only 121.6 oz of fuel.
I know folks in the forum are too smart for this!

 

[DAMIEN1307]

ratios are for oil poured into a gallon of gas.

I know folks in the forum are too smart for this!

You would mostly be correct...Most of us here ARE too smart to make the mistake of pouring the oil in first and then fill to the gallon mark...lol.

My fuel is ethanol-free in marked gasoline containers that I actually prefilled with water to mark off where I have poured an exact 128 ounces for a true one gallon reading before ever using them for gas...lol.

Only then do I add the exact 6.4 ounces of my Amsoil Dominator 2 stroke full synthetic oil along with one ounce of Amsoil Dominator Octane Boost since the only ethanol-free gas available in my town from only one gas station, is only 87 octane rated.

I then always shake the mix vigorously in the gas container so every time I pour gas into the tank it is fully mixed.

My motor runs beautifully on this mix

 

[ImpulseRocket]

I am smart enough to know that 2 stroke oil has a btu value close to gasoline, and good 2 stroke oil has a low flash point for a clean burn. In an engine like the phantom, and the stihl saws, they burn so efficiently that there is almost no smoke from them, even at high levels of oil mixture.

I am also smart enough to know that sweating a few ounces of gas when mixing is pointless.

 

[Chainlube]

You would mostly be correct...Most of us here ARE too smart to make the mistake of pouring the oil in first and then fill to the gallon mark...lol.

My fuel is ethanol-free in marked gasoline containers that I actually prefilled with water to mark off where I have poured an exact 128 ounces for a true one gallon reading before ever using them for gas...lol.

Only then do I add the exact 6.4 ounces of my Amsoil Dominator 2 stroke full synthetic oil along with one once of Amsoil Dominator Octane Boost since the only ethanol-free gas available in my town from only one gas station, is only 87 octane rated.

I then always shake the mix vigorously in the gas container so every pour into the tank is fully mixed.

My motor runs beautifully on this mix

I put my oil in the container first, but then I put in the correct amount of fuel right after. I don't go by what is marked on the container.

 

[DAMIEN1307]

There is less gasoline in a higher(lower#) mix

Just to be clear then as this is still not worded quite right as to be understandable to others that may read this.

20:1 mix means that the mix is 20 parts of gasoline to 1 part, (6.4 ounces) of oil...20 parts of gasoline for every 1 part oil.

 

[Cannonball3]

I am smart enough to know that 2 stroke oil has a btu value close to gasoline, and good 2 stroke oil has a low flash point for a clean burn. In an engine like the phantom, and the stihl saws, they burn so efficiently that there is almost no smoke from them, even at high levels of oil mixture.

I am also smart enough to know that sweating a few ounces of gas when mixing is pointless.

This is for all intents a hypothetical discussion. But the theory is sound.

Damien
You are doing what is safe with your build, good for you! What ever works that you are satisfied is what you need to do.
However I find it a bit Ironic that a 21century engine would need to run the same amount of oil as my antiques. Both the Maytags and the Villiers run 20:1, I boosted the Maytags up from 16:1 The only bearings in these engines are the rollers on the Villiers big end. The rest are bushings. I run a mix of 2stroke and 30wt, 5oz 30wt 1.5oz two stroke. Mainly to help with port clogging.
All that said, I never mean to sound negative in discussions. I just offer thoughts. Im not stupid enough to BS here. Yall are way too smart. I dont mind being corrected, thats how we all learn here.