I just bought a '06 YZ450f, and the jetting was all screwed up becuase the previous owner installed the slide plate upside down I went ahead and did the o-ring mod while I had the carb out, figuring I could always take it off later. Got that slide plate installed correctly, and took it for a test ride today around the neighborhood, it felt pretty good jetting wise, except there is a little stumble when I whack the throttle open quickly. The bike is all stock motor and exhuast wise, and it's set up for supermoto (if that matters) current jetting is: 48 pilot fuel screw 2 turns out 168 main stock needle in 4 th position stock 55 leak jet o-ring mod boyesen quick shot twin filter with no toil and back fire screen removed I'm in portland, OR at sea level and it's about 63 degrees right now, bike had very little decel popping (thinking about trying a 45 pilot) Since I never rode the bike before I did the o-ring mod, I'm not sure if that helped or hurt the situation, considering it has a quick shot on there. So should I try the 45 pilot? Remove the o-ring mod? Or do I need a smaller leak jet? Thanks!