I just had to drain the carb float bowl to empty out the sea foam-rich mixture. Problem is, several tanks of gas later, the same problem persists: the bike surges pretty bad when cold. I´ve been told this means it is running lean. So now I´m looking at grinding off the limiter cap on the pilot screw on my carb so that I can adjust the pilot screw for a richer mixture. Has anyone done this before?