I have a BME-102 that l have had for about 20Yrs that is the bast motor l've ever had. I bought it from a buddy of mine & was running Amsoil-100-1. I won a bottle of Am-50-1 racing oil. I ran out of my 100-1 & Tryed the 50-1moil. Now saying this, in my manual it says 50-1 Rec. Now this engine started knocking after a year of flying 100-1.,The frist tank wirh the 50-1 Racing, the crank let go, so l sent it back to BME & was charged $470 to rebuild it. I was also told l needed new cyl & pistons. I said GRATE, Do it! Well after about two weeks in the repair shop, l got my engine back & is had the old piston's & cyl's on it. I call & got a recording that that number was no good! I mean WT*? So l ran the enging &mit ran grate just line before, just with out the knock. Still is a grate engine, Not Happy About Paying $470 for A New Crank! but, l'll eat it. I was running a 26X10 prop but, it seemed aways was low on power (Having a Airhobbies-105 & a 3W-120) l tryed a 24X12 3D prop on (Engine was on a Hanger-9 330, 98" Ws) & it came alive & NEVER seemed to over RPM the motor. I still can't find the power reatting anywhere, So if anybody knows, please let me know. BME..... GRATE LITTLE MOTORS