Hi Anthony, you bring up some good points and underline some of mine. The change to N-D hub brake arms wasn?t part of my knowledge so I didn?t pick up on that. The chain ring on the bike doesn?t appear on Hawthornes until the spring-summer 1940 catalog.
The issue with dating a bike by anything other than the frame is that these parts may have been changed at any time. If the changes were made early on, the overall patina doesn?t prove or disprove originality. The bike may be sporting an earlier wheel set or a later chainring.
I agree that the frame in question typically can be dated to 1938-1939. It doesn?t appear after 1939 in Roadmaster consumer catalogs. The frames of this type I have encountered have all had Dxxxx serial numbers which I associate with 1938. I have a 39-40 style 5-Bar Zep and a 1940 style girl?s Supreme with Exxxx serial numbers.
As I have posted before, the earliest CWC frames I have found have Zxxxx serial numbers, followed by Axxxx serial numbers. The A, B, C, and D, and E serial numbers seem by model to fall into a straight forward pattern of alpha-numeric sequencing that would have started in 1935-36 and continued through 1939-40
I have found later prewar frames with F, G, H, and K serial numbers, some of which have additional stampings that seem to point to special stamping for some Hawthorne and Western Flyer production. I associate these numbers with 1940-1942 production.
The one standout oddball is an All American frame with a serial number A 15251 and an additional stamping (which appears to be factory) of a symbol followed by 138. In addition this bike is a Western Flyer not a Hawthorne.
I haven?t collected postwar CWC numbers, I believe some postwar numbers duplicate prewar numbers but, other than the earliest postwar production, those bikes are obviously later.
Anyway, my main reason for dating Akikuro?s bike as late as I did was on the basis of the H serial number. While 1941 was the introduction year for the CWC curved down tube, I believe straight down tube models may have continued in production as the basis for low spec. models offered to distributors.
Again, Anthony, thanks for your post; I have noted from your posts that you have a good eye for catching detail, (often ones that I have missed)
This is a lot about serial numbers. I have studied CWC and serial numbers for some time. Still this is only based on what I have seen and then conclusions the information has led me to. As more people post, my conclusions may be reinforced or prove incorrect.
Phil