I have a 1991 kx250 right now it has a 158 main jet air fuel screw at 3 turns out and a 52 slow jet.There is actually oil that comes out of the silencer onto the rear fender.The mixture is 32:1 and I am using a synthetic oil called golden spectro.I am only running this set up because this is how I bought it.Bike runs great but is kind of a hard starter maybe 8 to 10 kicks and she is running.First it pops out of the pipe once then a few kicks later its running. Dealer tells me main jet stock is a 155 my manual tells me it is a 175 thats a big diffference if you ask me,does anyone know what combination I should be running.I live in upstate ny ,and I mostly trail and field ride.Any input would be appreciated.