procarbine2k1
Addicted to ArboristSite
No the guy telling you this don't know ****. I find synthetic burns more complete, thus less carbon, the regular stihl oil you will carbon up more. But it takes a long time to carbon up a saw, keep it tuned right and you wont have a problem. If it starts getting carbon'd up you need to decarbon before it causes a problem. Most people abuse their stuff, and perform no maintenance, thus burning up top ends.
What he said!
I am surprised that your Stihl tech would claim that saws are "burning up" with a 40:1 mix, using synthetic! I run 40:1 in ALL of my equipment (Stihl Ultra), and will continue to do so. Premature failure with this setup is the least of my concern. If ethanol was not a concern, I may try 50:1- but is not the case with todays fuel.