I'm no authority on timing a sewing machine, but wonder if your problem is something else. Have you thoroughly cleaned, oiled and greased it? If you want to sew with a straight stitch, make sure the thread take-up lever is all the way up, set the Flexi-Stitch Pattern Dial to O for off. Select center needle position by pushing down slightly on the lever as you move it to center. Stitch Width should be set all the way over to the left for straight stitch.