1999 Yamaha 9.9hp 2 stroke popping sound at WOT

[merc16]

Hey guys, i recently picked up a yamaha 9.9 2 stroke, idles perfectly, i changed the spark plugs, water pump, gear oil ETC only thing i didnt take off was the carb cause the previous owner told me a shop just cleaned it.... anyways engine runs perfect but at WOT theres a popping noise randomly almost sounds like a popcorn pop/miss if that makes any sense, and it only does it from 3/4 to WOT... Anybody had any sort of similar issue?

Thanks guys!

 

[99yam40]

only popping noise I can think of would be a lean sneeze