I used the string method to check a frame that I wanted to buy. It ain't the best way , but it worked. The bike rides like a champ. I sent my Colnago(different bike) to Franklin Frame for a paint job and asked Jack if the alignment should be checked , it is a 1975 , after all. He said just what Gugie stated. If you've been riding it for a year and you haven't noticed anything peculiar , it is most probably fine.