The first AMF to get drop-outs was the balloon tire Flying Falcon introduced in June 1953. As far as I can tell, the Luxury Liner got drop-outs for 1954, although there were still some bikes offered that year with the rear fork. I think by 1955 all AMF bikes (Roadmaster and Shelby) were using drop-outs. This picture is a little hard to read, but it's from the 1955 Roadmaster catalog: "AMF Roadmaster's entire line features the drop-out rear fork. Rear wheel may be removed by simply loosening outside nuts - giving new ease and convenience in rear wheel repair and maintenance."
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