Hi guys. I have a US90 I picked up a few months ago and it has had issues running since then. It will idle forever but whenever a load is put on it or the throttle is floored, it bogs down and dies. It has a brand new 16mm Keihin carburetor on it that I purchased to replace the old identical carb it had on it because some parts were bad inside. There are zero exhaust leaks and all of the intake gaskets are intact. It doesn't foul spark plugs. The needle in the throttle is set for the highest gas ratio (I've tried it at all levels and the most gas worked the best). Would timing be an issue with this? Please help!