How I baby my 2 stoke motors.... 30-1 instead of 50-1

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For what its worth, I dont ever use any of the elite synthetic 2 stroke oils for chain saws, but I frequently use 2 stroke oils for outboard motors and conventional 2 stroke oils for air cooled motors meeting the min specs. What I do to baby my engines somewhat is I run all my mixes at 30 to 1 instead of 50 to 1 to assure a little extra lubrication to my
bearings and cylinder walls etc. while running and also to leave heavier coating when saws are idle. I would expect there to be excessive carbon buildup perhaps but so far I have not seen it. The saws seem to run just as well and
I dont really pay much more for oil as I usually buy it by the gallon.
Did anyone ever notice that all the bikes and saws used to be 32 to 1. I know oil quality has improved but the time they started switching up to 50 to 1 corresponded to higher emission standard and requirements. I always just kept mixing 32 to 1. it's easy that way because it 4 oz per gallon and the marks on the bottle are in 2 oz increments, not 2.6 oz. I have some old jonsered 670's that are running strong after 25 years.
 
Did anyone ever notice that all the bikes and saws used to be 32 to 1. I know oil quality has improved but the time they started switching up to 50 to 1 corresponded to higher emission standard and requirements. I always just kept mixing 32 to 1. it's easy that way because it 4 oz per gallon and the marks on the bottle are in 2 oz increments, not 2.6 oz. I have some old jonsered 670's that are running strong after 25 years.
All my older 70 & early 80 ' S 2T bikes ran 32:1 fine . Some of my European cycles Husquarna , Maico , Bultaco & Cz liked 24:1 better as far as making better base compression & max horsepower . The Japanese & Can-Am moto's pulled well with both 32:1 & 40:1 in Premix usage both in Mx & Enduro applications !
 
All my older 70 & early 80 ' S 2T bikes ran 32:1 fine . Some of my European cycles Husquarna , Maico , Bultaco & Cz liked 24:1 better as far as making better base compression & max horsepower . The Japanese & Can-Am moto's pulled well with both 32:1 & 40:1 in Premix usage both in Mx & Enduro applications !
We ran 25 to 1 in the old yz250 and kx250 bikes we had back when. Once we got into the mid 90's water cooled we backed down to 32 to 1 on the 250's and 125's, the cr500 stayed at 25 to 1. No idea why my brother kept running 25 to 1 in the cr500.
 
We ran 25 to 1 in the old yz250 and kx250 bikes we had back when. Once we got into the mid 90's water cooled we backed down to 32 to 1 on the 250's and 125's, the cr500 stayed at 25 to 1. No idea why my brother kept running 25 to 1 in the cr500.
Yeah , when you get into the bikes , its all about jetting . Pilot jet for a proper idle & off idle smooth acceleration . Then the transition to the main jet for a crisp throttle response without any lag . Proper sizing really could avoid having to down shift in numerous situations . Oversizing of the main jet could really effect operating temps & potential for spooge & exhaust side skirt deposits !
 
Mixed up some 32:1 since i have been cutting some big stuff with my husqvarna. I hope it likes it since the oil is old like the saw
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lol. That's about the vintage of FC that my Shell 2T was I ran in my Cz & Husquarna 250's . Bet it smells the same too ;)
 
Did anyone ever notice that all the bikes and saws used to be 32 to 1. I know oil quality has improved but the time they started switching up to 50 to 1 corresponded to higher emission standard and requirements. I always just kept mixing 32 to 1. it's easy that way because it 4 oz per gallon and the marks on the bottle are in 2 oz increments, not 2.6 oz. I have some old jonsered 670's that are running strong after 25 years.
Yamaha still specs 30:1 for their two stroke bikes.
 
Please explain what do you mean more power? How does running 100:1 make more power?
Oil displaces fuel. Displaced fuel = a lean air / fuel mixture. Lean mixtures don't make power. This is more a factor on non-adjustable EPA carburetors, but for a given air / fuel mixture, a leaner oil / fuel mix results in a richer air / fuel mix.

I run every 2-stroke I own on Saber at 100:1, except for my paramotor - I run that at 66:1. Not because I'm afraid it'll seize, but because it was advice from someone with much more flying experience than I have that runs a paramotor school (and a pharmacy), and owns & repairs several paramotors. Just easier to follow someone else's lead in this case.

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Oil displaces fuel. Displaced fuel = a lean air / fuel mixture. Lean mixtures don't make power. This is more a factor on non-adjustable EPA carburetors, but for a given air / fuel mixture, a leaner oil / fuel mix results in a richer air / fuel mix.

I run every 2-stroke I own on Saber at 100:1, except for my paramotor - I run that at 66:1. Not because I'm afraid it'll seize, but because it was advice from someone with much more flying experience than I have that runs a paramotor school (and a pharmacy), and owns & repairs several paramotors. Just easier to follow someone else's lead in this case.

View attachment 1030347
What you describe and what you acknowledge in regards to oils effect on air to fuel ratio is vastly surpassed by changes in ambient temperature.
 
Not talking about temperature, or ANYTHING else. The question was, how a leaner oil / fuel mix makes more power. I explained that.
 
I like giving people crap for thinking extra oil is good. I just never hear much on people adding more oil on a 4 cycle. What I seen on both engines if you add to much oil it just blows oil out every ware. I have a few Tecumseh 2 cycle engines the gas cap read 32 to 1 I mixed it that way. I would say the muffler should never rust out .For decades I just made one mix for all 2 cycles my old Lawn boy I start with either. I do have a clue about 2 strokes back in my outboard days I would hear a new camshaft would make it faster. And there was the fraction thing 50 to 1 was more than 32 to 1
Not if you tune your equipment I run all my equipment new and old at 32 to 1 and tune it for such. As a matter of fact my Stihl kombi tool was blowing extra oil out of the muffler from the dealership when it was running 50 to 1 bc 1 I was using the recommended Stihl oil(junk) and 2 think it was tuned rich.
 
They don't.
As you get leaner you will make more and more power until you seize. A 2 stroke will seize before you get leaner than stoichemetric in most cases.
Any mixture lower than a ideal stoich (14.7:1) air / gasoline fuel ratio is considered rich , which usually produces more horsepower & a cooler engine . Anything higher will be considered a lean mixture producing more heat & potential for oxide emissions & eventual seizure in my observations . Its a rather fine line & my experience more often involves Industrial air / fuel calculations with various fuel densities such as methane , propane coke oven gas & various heavy C fuel oils. So , I think Ben has a more accurate understanding of required air / fuel enrichment potentials & effects within a basic 2 T calculation . I would follow his lead !
 
Any mixture lower than a ideal stoich (14.7:1) air / gasoline fuel ratio is considered rich , which usually produces more horsepower & a cooler engine . Anything higher will be considered a lean mixture producing more heat & potential for oxide emissions & eventual seizure in my observations . Its a rather fine line & my experience more often involves Industrial air / fuel calculations with various fuel densities such as methane , propane coke oven gas & various heavy C fuel oils. So , I think Ben has a more accurate understanding of required air / fuel enrichment potentials & effects within a basic 2 T calculation . I would follow his lead !
It's the whole what should happen in theory vs what actually happens.
 

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