40:1 instead of 50:1?

[Thomas Lilli]

With regard to mix oil, I’d suggest you would have to know more about mix oils. Flash points are all over the place, and film characteristics vary greatly per degree of temperature from one oil to the next. Synthetic vs mineral etc. 

I also understand that, because of the environmental considerations, manufacturers make design changes that make them run, inherently hotter (intake air stratification vs exhaust stratification) and therefore leave a larger range of fit between piston and cylinder compared to saws of 10-15 years ago. This all comes into play when you contemplate mix oils in my opinion. 

The man that builds my saws recommends a 50:1 full ester synthetic mix oil and he’s done extensive tests with those oils as a pro northwest faller and builder. My saws are designed to run on highest octane possible, Motul 800 2T factory line road (or equivalent) mix oil at 50:1. They’re obviously high compression and the 461, revving a bit higher than factory. He builds them for falling and, the amount I cut per year, I’m sure they outlive me.  

Incidentally, I pulled the plug on my 461 just to borescope the cylinder and everything inside was pristine, not a mark on the cylinder. The piston top only had some erosion marks from gas flow at the intake and exhaust ports. 

Good discussion. 

[Al_Smith]

The resurgence of a 15 year old thread concerning the great oil debate .  --gotta luv it ---

[Old Greenhorn]

Some horses won't die no matter how hard you beat them. 

[Reddawg]

I was a Stihl Ultra 2-cycle oil user while my 461R was under warranty. Found 50:1 to leave some deposits on the piston and exhaust. Nothing major but it’s new so I wouldn’t expect much either.
Switched to a recommendation from a pro saw builder and faller of big wood, Motul 8002T at 42:1, since 3oz per gallon mix in the field is easy to do. After a bit of fine tuning from the factory setting, I see a better burn of the fuel mixture with the piston cleaning up and the plug dry and slightly brown on the electrode. 
On the big saws and the small ones I run the same mixture with 89 gas that has ethanol in it. No place close to get pure gas. I don’t have any issues at all, knock on wood, and would recommend a bit more lubrication than less. These saws work really hot in the hardwoods so be kind to the saw and it will reward you for a very long time.

[Canuck123]

Definately Gotta love , the oil ratio threads . I agree with Stihl Doc & Saw Guy that 50:1 with modern synthetic oil will protect today's & yesterdays saws . It's simple ,  improved oil technology . Mr Walker is correct within proper tuning and xtra oil can improve horsepower in racing scenerio's however in the hobby woodcutter life may cause additional carbonizing of the exhaust ports and piston rings . This is due to lower operating temps of consumer saws vs professional saws with high compression and rpm operating ranges. I run Sabre & Motul T at 50:1 on most applications , in certain saws I run 44:1 while milling or bucking . Anyhow good discussions , long live the oil threads !

[barbender]

You love oil threads so much you had to drag up one from a year and a half ago?😁

[welderskelter]

I was out of gas in the mill yesterday and all I had was chainsaw gas. So my 17 hp. kohler runs good at 30 to 1. I was surprised it didnt even smoke. Which reminds me I should lean it out on oil now that I got some more gas. I can remember when I was about 16 dad had a remington and I had an old mono. We bought our oil in town as bulk oil. Dad bought a 2 gal. can of hydraulic oil. When we needed some for the tractor we figured out we had used it all up for the chainsaws. Dont know that it hurt them any.

[Canuck123]

You love oil threads so much you had to drag up one from a year and a half ago?😁

Hell , would you prefer from 10 yrs ago ? Actually  , enjoy the various opinions ! 

[Canuck123]

I was out of gas in the mill yesterday and all I had was chainsaw gas. So my 17 hp. kohler runs good at 30 to 1. I was surprised it didnt even smoke. Which reminds me I should lean it out on oil now that I got some more gas. I can remember when I was about 16 dad had a remington and I had an old mono. We bought our oil in town as bulk oil. Dad bought a 2 gal. can of hydraulic oil. When we needed some for the tractor we figured out we had used it all up for the chainsaws. Dont know that it hurt them any.

I would like to see how one of the new computerized saws would react to straight 30 @ 30:1 

[barbender]

I think they would get confused😂

[thedoublejranch]

I either buy the pre mixed gas in gallon cans or when I do mix, its 3oz to a gallon leaving me with 44:1, 3 oz is a nice number vs 2.6oz etc.

[sawguy21]

That works for you and it's fine. Simple and easy to remember. Being under the metric system I mix 100ml of oil to five litres of gas for 50:1, don't ask me to figure it out under the British standard system which I have forgotten.

[Tacotodd]

People just need to remember it in EASY terms; 50 PARTS gas to 1 PART oil. Easy Peasy  

[Ianab]

People just need to remember it in EASY terms; 50 PARTS gas to 1 PART oil. Easy Peasy  

While that's 100% correct, 5,000 ml (5 litres) of gas, with 100ml of oil is much simpler maths than figuring ounces of oil to gallons of gas. 
Under metrics the PARTS are basically in the same units. 

[barbender]

I like metric, I hate fractions.

[sawguy21]

It is easy to work with once we learned to THINK in metric and stopped trying to convert. My mother refused to use it, maybe because her parents were American.

[HemlockKing]

It is easy to work with once we learned to THINK in metric and stopped trying to convert. My mother refused to use it, maybe because her parents were American.

Us Canadians are “mixed”. Typically use imperial for height and weight of person. Metric measuring liquids, metric speed limit, imperial construction materials. I’m pretty sure the us fed gov officially switched to metric with Canada though back then

[barbender]

Mixed is the worst, in my opinion. Give me one or the other. At work, I operate a Finnish built forestry machine and it's all metric, all day long. I keep metric tools on it, there's never a question of what tools you need. Unfortunately, a lot of American stuff you can find both metric and standard on the same vehicle. It makes for a lot of trips back to the toolbox.

[HemlockKing]

Mixed is the worst, in my opinion. Give me one or the other. At work, I operate a Finnish built forestry machine and it's all metric, all day long. I keep metric tools on it, there's never a question of what tools you need. Unfortunately, a lot of American stuff you can find both metric and standard on the same vehicle. It makes for a lot of trips back to the toolbox.

Yeah try being a machinist  like you said it’s a pain. 

[sawguy21]

I ran into it on a mid 80's GM pickup, the bolts holding the crossmember to the frame were British standard but the transmission was metric. How stupid is that?