A little muffler mod on my 555 this afternoon.

On a stock saw.. Yes. On a ported saw that is making more power and has more pressure on the bearings, crank, rod, etc? I will use the extra ounce of oil. Think about how miniscule of an amount that is, compared to a gallon.

All equipment used to be 25:1 - 32:1 until several years ago. The EPA is the reason it's leaned out.

I run 36:1 using my Ratio-Rite cup. No smoke, better ring seal as stated above, and my saws look oily when opened up.

A 50:1 saw will look dry inside of the muffler. Not enough oil for my liking.

You can also use a lower rated octane level. 93 isn't necessarily better for the saw. Remember, the higher the octane rating, the higher the auto ignition point is (meaning it takes longer or hotter Temps to ignite). Lower octane fuel has a lower ignition temperature (not to be confused with its flash point. Gasoline in general has a very low flash point)

This is probably gonna open up a can of worms

I should start a poll. I think the general concensus is to run higher octane. But it is not needed at all. 87 is just fine and will not "dirty" your engine or make less power.

 

Yep. The "High" octane in ways may be worse.

Higher octane in a chainsaw isn't what it's cracked up to be. As you seen Hedge and Mdavlee talk about above.

87 is always fresh. A small mom and pop place may sit on 93 for a long time. And if it is a 10% Ethanol mix?? After sitting for an extended period of time, ethanol fuel absorbs more moisture/water.

Run what you want. I don't push anyone to run 87 or run a thicker oil mix. But people need to be informed of the pros and cons to using a high/low octane fuel and a high/low oil mix.

 

So long as your saw is still exactly as Stihl engineered it, 50:1 will not blow it up. But many of us have added power in one way or another and know that 50:1 is marginal. More oil will contribute to better ring seal and make more power in addition to better lubrication and cushioning of shock loads in the bottom end. And today's modern synthetics will not increase carbon build-up within the engine. Quite the opposite actually.

One engine builder put it this way, "it's not the piston seizing in the bore that worries me (with 50:1), it's the bearings in the bottom end."

 

You guys are all way ahead of me on this one.... Lol.

"Premium" fuel usually isn't...... Engines run their best on the very minimum octane required to stop detonation/pre-ignition.

The exception is if you live in an area where premium is ethanol free, then by all means go that route as it's worth a bunch more power than the miniscule amount lost to the excessive octane rating.

 

Amen..