THE OS MOTOR HAD OVER 2 GALLOONS THROUGH IT.THE X12 HAD OVER 3. I'VE BEEN RACING FOR OVER 4 YEARS,ALWAYS HAVE USED MUGEN OR BYRON FUEL WITH NO PROBLEMS.MOVED TO FLORIDA COULDNT FIND MUGEN OR BYRON. IF I DID IT WAS $30 A GALLON TRIED WHITELIGHTING ON A RECOMENDATION .I KNEW IT HAD LESS OIL SO I RICHENED IT UP AT LEAST 1.5 TURNS LET ENGINE IDLE HALF TANK RAN REST VERY EASY ALMOST LIKE A BREAKIN. THEN STATRED TO TUNE ENGINE RAN AT ABOUT 200 BUT STILL NOT THE SAME POWER AS BEFORE BUT I DIDNT WANT TO BLOW IT . WELL IT STILL BLEWUP .EMAILED WHITELIGHTING GOT THE MOST DUMB-ASS RESPONSE . THAT I USE IT FOR CLEANING MY ENGINE PARTS NOW.I WILL NEVER BUY OR RECOMEND TO ANYONE.AS FAR AS IM CONCERNED ITS CRAP! IVE HAD MOTORS LAST ME THROUGH 7-8 GALLONS BEFORE NEEDING REBUILD.AT RACE TUNE!BEEN TUNING MOTORS FOR SOME TIME,SO TUNING WAS NOT AN ISSUE