I have the same issue with the sputtering at light load conditions. It does it at a steady state cruise in 2nd and 3rd gear @ around 3500-4500 but not all the time. Its quite annoying honestly, almost seems like a misfire. Their was another member of this forum that was having the same issue and he said it was resolved after changing out the ignition coils. I haven't made it that far yet, plan on tearing the bike down soon.