2 Stroke Fuel Ratios: Is 50:1 Good for All OPE?

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I have old OPE. Lawnboy mower that's 32:1. Homelite saw that's around 24:1 if not using Homelite oil. Newer stuff is all 50:1. Is is really necessary for all these different mixing ratios, or is the 50:1 oil that's made now good enough for everything? Thank you gents.
 
I've been told that the ratio was based on the oil's capabilities at the time. 50:1 is standard today and should be fine in everything.
I mix Amsoil sabre at 100:1 for my equipment as per the directions and haven't killed anything yet.
 
Originally Posted By: mechjames
I've been told that the ratio was based on the oil's capabilities at the time. 50:1 is standard today and should be fine in everything.
I mix Amsoil sabre at 100:1 for my equipment as per the directions and haven't killed anything yet.


This.

I have customers running 50:1 ratio in older machines calling for 32:1, and they run great. Oils have improved greatly.
 
I think lawn-boy says 32:1 because they call for use of an ashless outboard oil. I wouldn't be afraid to use an FD rated oil in the lawn-boy and other equipment at 50:1. The Poulan brand at Walmart in the garden center is where you'll find that for $1.38 a bottle. It's not in the auto section with the Supertech two-stroke oils
 
depends

Some older has plain bearings. It needs 24 or 32 to one.

Most newer all roller or ball bearing can use at least 40 to one.

I never use 50 to one.

Rod
 
I run 32:1 in everything 2 stroke except for the big chain saw (16:1), 40 and 50:1 is for emissions which they can shove where the sun doesn't shine. Let the smoke out!
 
Originally Posted By: Trav
I run 32:1 in everything 2 stroke except for the big chain saw (16:1), 40 and 50:1 is for emissions which they can shove where the sun doesn't shine. Let the smoke out!


Reminds me of a talk we had recently.
wink.gif
I'm going with 32:1. I was running engines that call for 40:1 at 32:1. I recently bought a trimmer that calls for 50:1, now everything I own that runs TC oil is running at 32:1.
 
Originally Posted By: ragtoplvr
depends

Some older has plain bearings. It needs 24 or 32 to one.

Most newer all roller or ball bearing can use at least 40 to one.

I never use 50 to one.

Rod


+1 It depends on the design and metallurgy ... I belong to a vintage chain saw group. Some of the old stuff absolutely will not run right on lean mixes ...

If motor calls for less than 50:1 you can arrive at some balance and run all your gear there. I'm happy at about 36:1 for everything. It's a convenient number given my old Eagle cans and mix bottles.

No engine ever died from too much oil. Some have from too little ...
frown.gif


Some of the old plain bearing reed valve motors need to be wet ...
 
Originally Posted By: demarpaint
Originally Posted By: Trav
I run 32:1 in everything 2 stroke except for the big chain saw (16:1), 40 and 50:1 is for emissions which they can shove where the sun doesn't shine. Let the smoke out!


Reminds me of a talk we had recently.
wink.gif
I'm going with 32:1. I was running engines that call for 40:1 at 32:1. I recently bought a trimmer that calls for 50:1, now everything I own that runs TC oil is running at 32:1.


Same with me. My son has a YZ250 dirt bike that uses Amsoil Dominator at 32:1, so that is what everything gets now and they run just fine and don't seem to smoke anymore than 40 or 50:1. The leaf blower really rips on the VP race fuel!
 
It isn't all about the oils ability to protect at lesser ratios though. You have to factor in Jetting. The metering orifices and/or jets if it has any are calibrated to work at what the factory set the ratio at. Many folks don't realize that when you go from 32:1 to 50:1 you are using less oil but MORE fuel available in a given amount making the engine much richer than planned, fouling plugs and killing mufflers/spark arrestor screens.

At 32:1 the carb/engine is expecting XX amount of gasoline in the incoming fuel charge. At 50:1 there is significantly less oil!

Studies have been done on two stroke engines showing more power and ring seal is present at mix ratios all the way down to 10:1, so less oil is not always a good thing! Leave it to the EPA to mandate 50:1 and 60:1 ratios at the expense of power and engine life.
 
Originally Posted By: racin4ds
It isn't all about the oils ability to protect at lesser ratios though. You have to factor in Jetting. The metering orifices and/or jets if it has any are calibrated to work at what the factory set the ratio at. Many folks don't realize that when you go from 32:1 to 50:1 you are using less oil but MORE fuel available in a given amount making the engine much richer than planned, fouling plugs and killing mufflers/spark arrestor screens.

At 32:1 the carb/engine is expecting XX amount of gasoline in the incoming fuel charge. At 50:1 there is significantly less oil!

Studies have been done on two stroke engines showing more power and ring seal is present at mix ratios all the way down to 10:1, so less oil is not always a good thing! Leave it to the EPA to mandate 50:1 and 60:1 ratios at the expense of power and engine life.

You are correct Sir!
 
I run my LawnBoy 10227 and 22261 2 stroke mowers on Amsoil Saber at 50:1 even though both say on the fuel cap to use 32;1 Never had any problems with either.
 
50:1 with E0 fuel. Weed eater, chainsaw, and leaf blower.

The 2 stroke LB's are in storage so no worries there.
 
I have an old chain saw, its loves 16:1. If it has a separate oil tank yes re-jetting will be necessary but everything I have is just mixed in with the fuel so it doesn't seem to matter, they definitely run wetter.
 
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