It's definitely a Monark. Same frame, chain wheel, and rack as this one.
And it is 50's. "Monark officially shut down the Chicago plant at 6501 W. Grand Avenue in 1958"
The tag attached numbers go into 1954 and the last number was 1,911,106. After that I can't find anything. So, I'd say it's 1954-58 bike. Huffy made them later, but with an H serial number and their chain wheels, so it's not Huffy made, it's Monark. The tags were riveted on so two small holes would show if it was removed. Your numbers are 8A268 and 2,485,087. The first was probably the model and the second numbers the sequence number. That would put your bike 573,981 bikes after they stopped using the nameplate. Using the 50's numbers, Monark made approximately 400,000 bikes a year. 1956 or 57 would be my guess as to the year of your bike. All guessing.
I'd fix it and ride it.
And it is 50's. "Monark officially shut down the Chicago plant at 6501 W. Grand Avenue in 1958"
The tag attached numbers go into 1954 and the last number was 1,911,106. After that I can't find anything. So, I'd say it's 1954-58 bike. Huffy made them later, but with an H serial number and their chain wheels, so it's not Huffy made, it's Monark. The tags were riveted on so two small holes would show if it was removed. Your numbers are 8A268 and 2,485,087. The first was probably the model and the second numbers the sequence number. That would put your bike 573,981 bikes after they stopped using the nameplate. Using the 50's numbers, Monark made approximately 400,000 bikes a year. 1956 or 57 would be my guess as to the year of your bike. All guessing.
I'd fix it and ride it.