November 1982 Chicago USA built frame Schwinn Cruiser, Serial # LT558151 on headtube, Head Tube is 5 3/8 between crowns. Originally Takes Schwinn S7 wheels 16" x 1.75".
You could put S2 or standard 26 beach cruiser wheels on this bike, but not with fenders, too tight of fit. See detailed photos provided for your review.