The correct carb adjustment is Low Speed 1 1/4 turns and high speed is "0". Have you done a spark plug check? how do the spark plugs look? Are they new and gaped properly? It is possible that the jet pump might be binding also. Did you do the install yourself? It's seems funny that after some maintenance it isn't as good as before. Just verify that all the items touched were done properly.
Have you done a compression test also to be sure all is well internally in the engine? Here is some information on a compression test.
You'll need a compression tester. Go to Auto Zone. I think they sell for like $25.00. The compression gage, will screw in the cylinder head in place of the spark plugs. To test compression, remove both spark plugs. Place spark plug caps on the plug cap studs near the cylinder head to ground the empty caps. This completes the circuit of the ignition electrical system and prevents any electrical problems from the caps being un grounded. Using the correct adapter for the threaded end of the tester,( same length of the spark plug threads length)screw in the tester in one plug hole. Hold the throttle wide open. Push the start button. Watch the compression gauge, when it peaks out at the most compression, let go the start button. Read the psi number. I would do it 3 times to be sure it is accurate. Check both cylinders the same way. The ideal compression is 150 psi per cylinder. If it is less, it's not a problem as long as they are close to being the same. If the psi is less than 90 it might need be time for a tear down and a rebuild. If the psi in 1 cylinder is say 140 psi and the other is 80 psi you need to tear down and repair. This difference is a lot then there is a problem. I hope this helps you.
Karl
