2 Stroke: 40:1 or 50:1

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About a year ago, I read through a posting about the mixing of 2 stroke and the proportions... Either here or arborsite - can't recall

Some went as thin as 100:1 and others said they still go 32:1 regardless of what the mfg states. The 16:1 or 32:1 group felt more power (compression?) was obtained and, despite a smokier run, was overall better for the OPE

Just curious what impact might be caused by running 40:1 in an Echo weed whacker, blower or chainsaw all of which call for 50:1.... Would I be creating a maintenance issue for myself?
 
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When I was production cutting with a saw alot of people were going 40-1 instead of 50-1 for added durability to the rings, they would last alot longer.
I took this advice and never had a ring related problem in 3 seasons.
That is just my experience.

E anything will kill 2 stroke power.
Make sure you use pure gas and mix it by shaking vigorously the can of mixed fuel every time you use it, dont store fuel in your power equipment let it idle dry.
Never had a problem with my 2 stroke power.
Cheers.
 
In addition, the 40:1 ratio creates a better piston ring seal resulting in more power and a smoother / quieter running engine.
 
Koz1.., there's a small airport fairly close to my home. One of these days, I'm going to stop by and see if they sell Avgas... Otherwise, virtually no non-ethanol to be had for many many miles. I was going to run either the Trufuel or Echo mix but the thought of $25 - $30/ gal just makes me angry

147_Grain...that's along the lines of what I recall being said. But I have to assume that you can go overboard? Say a 32:1 or even 16:1... Wouldn't that just get messy after a while? Start clogging things up?
 
Do you think going from 50:1 to 40:1 would require a carb adjustment? I suppose so... Easy enough, right?
 
I've always mixed an oily 32:1. My Farm Boss is 38 yrs old. It wants Stihi mix at 40:1. Never had any carbon fouling. I add a little MMO so the smoke smells good
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I just mixed up a gallon of 93 octane E10? and 4 oz of Valvoline Universal 2 stroke oil. The old 50:1 Mantis likes it. I haven't adjusted the carb on any of my 2 strokes to accountfor the extra oil.
 
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Experiment a little with the ratio to fine-tune things unique to your equipment, quality of fuel / 2-cycle oil, and altitude. A clean carburetor, combustion chamber, and spark plug (gap ?) Matters too.
 
Originally Posted By: 147_Grain
Experiment a little with the ratio to fine-tune things unique to your equipment, quality of fuel / 2-cycle oil, and altitude. A clean carburetor, combustion chamber, and spark plug (gap ?) Matters too.


So true, spark plug gap widens the more you use it.
I changed plugs every season.

Marine fuel is pure gas as well.
 
Originally Posted By: Finz
Do you think going from 50:1 to 40:1 would require a carb adjustment? I suppose so... Easy enough, right?

After break in take it to your dealer for a tune up have 40-1 mix in the tank get them to do it in front of you, only a couple bucks.
You can kill a saw very easy with lean condition.
 
Home Depot for all the OPEs... I wouldn't stand a chance

I'm comfortable taking a stab at it, though
 
My Stihl ope calls for 50:1, I have been mixing 40:1 using Stihl Ultra synthetic. IMHO, the 40:1 will give better engine life, and I have seen no ill effects. Spark plugs and piston crowns still seem clean.
 
I think 40:1 is a very good ratio. I never had a problem with 40:1 or 50:1 in my trimmmers or chain saw. I use ELF syn 2 stroke oil I found on clearance at a local cycle shop. I bought the last quart for $6 and it'll last me forever.
 
Originally Posted By: Finz
About a year ago, I read through a posting about the mixing of 2 stroke and the proportions... Either here or arborsite - can't recall

Some went as thin as 100:1 and others said they still go 32:1 regardless of what the mfg states. The 16:1 or 32:1 group felt more power (compression?) was obtained and, despite a smokier run, was overall better for the OPE

Just curious what impact might be caused by running 40:1 in an Echo weed whacker, blower or chainsaw all of which call for 50:1.... Would I be creating a maintenance issue for myself?


Throwing a wrench into this conversation, I'm still waiting for several OPE to "blow up" as I was told here by many using Opti-2 at 100:1 in fact, they start easy, they run smooth, no smoke, I haven't put a compression tester in them but they do feel like the compression have been creeping up but it could be that I want to feel that, all of them have 100 hours + of operation at full throttle; the oil has stabilizer for a two year stint, granted is not that easy to find in a lot of places, just another option to consider. I have also tried Amsoil Saber Pro. with good results at least in a very short term from 100:1 to 60:1 but somehow I prefer the Opti-2. Just my 2 cents.
 
Originally Posted By: Donald
Unless you burn a lot of gas, the premix seems fine. I burn a couple of quarts.


Home Depot runs a BOGO on Tru Fuel once or twice a year. I bought 12 quarts a year ago February and have used my 3rd out of the lot.

Problem you have with any OPE made in the last 6-7 years is they have catalytic converters. Running too much oil can clog them...easily fixed but still a hassle.
 
I forgot to add, If you can get that ethanol free gas (have you checked Pure-Gas.org?) going from 50 to 40:1 shouldn't present any issues and tuning will be OK if it is good using 50:1/10% ethanol gas since the mixture will go leaner with more oil but without the ethanol in the gas the caloric content of the fuel will be higher actually enriching the mixture and thus compensating more or less the leaning from the extra oil. Now, be aware that for quite a few years already the carbs. are coming either non-adjustable or you will need special screwdrivers to turn the needles, I have had to buy those screwdrivers because with a combination of 100:1/ethanol free gas the engines were running rich and besides that I use them year round and here that means from the 30's to 100's F. Another point to remember is that if you use a good quality oil even at 50:1 it is most likely that the rest of the equipment will fall apart long before the engine even starts to loose compression, filter the fuel "before" pouring it into the OPE and keep it fresh. Best of luck!
 
It depends on your 2-cycle oil.

I have found some formulations require a 60:1 ratio (in a 40:1 spec) because of the chemistry used.

I increase the fuel to oil ratio until I hear that lean-out "popcorn" sound.
 
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Was reading an Opti-2 thread here not long ago, and that could be what got me to thinking about this more maybe...?

If only I could find that earlier thread... Was numerous pages with all sides represented and no point of view was forcefully discounted

Wish I knew more about this stuff...
 
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