Justin Hopkins
ArboristSite Lurker
I run everything I have on Amsoil Saber 80:1. Now my dad ran stihl original orange mix 50:1 in his but I also remember him going to saw shops and having carbs rebuilt and motor work done. I'e used my ms660 36" bar in -5 to 102 and it' never failed me it's 7 years old. Less oil with the same protection why not. My step dad was a gas station tech for 22 years and if he says don' use 91 because of moisture content I just don' use it. Amsoil has it on their website it' guarantee to protect all mix ratios. I used to have nasty black residue leak all over the front of my saws and now I don't. Even if u mix it at 50:1 it' just a better product all around. Just my humble opinion.Justin, welcome to the site. You managed to get me again, an 11 year old thread. I'm retired from a 4th generation tree service. The OP, who only posted once, was concerned about a 70's Mac. All of your equipment is pretty much brand new and designed to run on 50:1. What do you run your old stuff on? I had an old Homelite 7-29 that was designed to run on 10:1, doubled as a mosquito fogger. I was just messin with you a little. We sometimes go off the deep end on oil mix threads. Again, welcome aboard, Joe.