2010 50 running lean

[ace75]

Bought a used 2010 50 last year with aluminum cyl, 21 pwk carb, unifilter and he said a 70 pipe. It came with a 108 main 38 pilot and air screw at 3/4 turn out. I bought last October and my boy rode it alot with zero issues. This year it's running very lean on wide open throttle. Plug is grey even with a 118 main. I even pulled a 142 main outta our 90 and that finally turned plug black. Is it possible for jetting to be in the high 120-130 ish. We are at sea level and 10 celcius today. Or is something wrong?

[Longdong]

Could be sucking air in somewhere....... Cracked boot?

[ace75]

I am building a leak down tester at work and need to stop at autoparts store for a freeze plug, does anyone have the size of freeze plug needed for exhaust port?

[nastynotchback1]

Probably crank seals.

[selbygirl]

if your boot is leaking , take some carb cleaner and spray around there while its running if the idle rises then its leaking , some times the reed cage boot gets warped or cracked , like sed in the other post . you could use a pipe plug the one with a wing nut plummers use them homedepot or lowes. or a boat plug . or make a plate with a gasket use the exhaust flange