Home Forums Shifter Karts CR125 Too Lean? Reply To: CR125 Too Lean?

Jimmy McNeil

20 to 1 is a rich mixture (even for road racing) and may even be contributing to the speckling your seeing on top of the piston. Think that comes out to 6oz per gallon, go to 4.5 or 5 oz. Running a rich fuel/oil mixture = leaner in the combustion chamber. The popping your hearing is common with a lean condition.