To reply to The mobil 1 racing 2t carbon deposits, I have never had a carbon deposit problem with this oil. You might want to run less oil to lean it out. Mobil one will run as high as 100:1 but I have never run it over 80:1 and I never have had any noticable deposits except slight deposits on the center of the top of the piston. Its the only oil that I ever used that I dont even get shiny spots on the piston skirt let alone scuffing. I have talked to engineers at 4 of the major engine makers and they all say to run a gallon or so of NON synthetic first, before using the good oil. They have refered oil for this as Stil, Husky, or any other quality NON. Like I said in my original post Mobil one has stoped making 2t, so go get some while you can, Auto Zone carries it at most stores.