thnx goat i was going to run 80:1 but if you say the manufacturer calls for 50:1 that is what im going to do, i spent to much time and money on this engine to fry it just cus i leaned out the oil fuel mixture, now on another note i got the clutch to work with the old brass bushing and what i notice is everytime i fire it up and take it for a ride the first enitial wot the bike take off like a bat out of **** right of the go but every time after that it feals like my 2 shoe clutch, the engine revs nice and healthy the clutch slips as it should and i slowly make it up to speed till i hit higher speed than i feal the clutch lock up and off i go with a grin on my face, now my only explenation for this is new clucth and maybe the fricition material isint quite soaked in and it feals like the clucth is maybe dry that first enitial pull thats why it grabs so good (less oil to lubricate as the oil settles to the bottom over night),