new wr owner, just removed air pump , used the yamaha kit, done the full mod, exhaust tip,airbox restricter, grey wire. now it pops and burbles under decelaration, followed directions, used 48 pilot,supplied needle, no other jets, air screw 2 turns out. runs good , but annoying pop , also tried 06 yz muffler and it made the super loud pop and foot long blue flames, am i too lean on main jet??? took yz muffler off as it was machine gun popping bad!! an new to 4 stokes after retiring the 90 cr500. please help!! dealer is a moron.only thing i didnt do is cut the airbox.