Discussion Starter · #1 ·
Ok, so I've got a 2000 400ex and it runs pretty well, the only thing is that on decel it has a lean pop. I believe its a stock motor with the full yoshi pipe with the header and a uni air filter. The airbox has 3 1-inch holes drilled into it already. I was in the carb and it has a 142 pilot and 150 main. Do I need to go bigger on the main? How much bigger?