I use the Castor 927 full synthetic with the tan label, i run 6.5 ounces to 1 gallon of 91 for the first 300 miles, this 2 smoker oil smells good and runs really smooth with very litttle engine noise. After the break in i run 5 to 6 ounces, there is a shop in my town that is selling some type avionic 2 stroke oil and claims you only need 1-2 ounces of oil to the gal. Im going to go check this stuff out but am kinda weary if it will shorten engine life running so little oil.