I recently purchased two Toro weedeater motors off of e-bay. They are new but factory seconds. I converted one for airplane use. The problem is it won't rev past quarter throttle without falling on it's face. Since the motor is new it has great compression and is getting spark, so I know it's a fuel issue. I've taken the carborater completely apart and it doensn't seem to be plugged up, main jet, ect... I've removed the white plastic cap covering the low end needle adjustment. No matter how I turn it, in or out, it doesn't seem to help. The engine will idle all day long, no problem, but when I accelorate the throttle the motor wants to die. I'm mechanically inclined and have converted many motors but can't seem to crack this case! It's a two barrell model. Any help would be greatly appreciated!

Jon