Our new gas can gunk up a carburetor over the winter. It does sound like it's running lean. Sometimes you can remove the idle mixture screws and spray carb cleaner in the holes to dislodge the goo (or used compressed air) . You may have to rebuild your carb.
This is possible. I put some new gas before I fired it up. Also added dry gas in case moisture built up during the winter. Responses so far seem to point to the carburetor.
