Originally Posted by maniac57
Yes, it sounds like an air leak somewhere. I'd check the crankcase seals if you find nothing elsewhere.
I agree. The seal behind the magneto rotor (magnet) is highly suspect. If the factory doesn't drive the seal in corrrectly the rotor will rub it destroying it. I've seen a couple of those but members here have also found the right side seal behind the primary gear defective too.
If you're confident that you've sealed the intake and carburetor and you still have the symptoms you're describing then take a look at your crankshaft seals.