- Feb 14, 2007
My 1979 RM400 is just about finished and having a little problem with carburetion. I upgraded to a later mikuni with a larger 1/4 fuel inlet to get rid of the pee hole sized inlet that caused these bikes grief. First thing I noticed about the carb was I had to lower the fuel lever durastically to get it to quit slobbering out of the overflow. I would only leak while it was running i'm guessing because of the vibration? The float valve is brand new. I know the stock main jet is a #270 which is what I have, Slide needle #6jf6 on clip position #4, stock nozzle. However it seems to run extremely lean on the pilot circuit. The pilot jet I have in there is a #50 and i'm not sure if that's the right one. Could one of guys steer me in the right direction?