Unlike the Morrow and Musselman hub shells there is no date code on New Departure hubs. The first ND hubs were made starting in 1898.
Early Hubs were a straight pull hub and had large cast brake arms. These were contracted by ND but built by Corbin. Before the Model A was introduced these hubs transitioned to the traditional spoke hole.
The Model D was made from 1934-1959 and there were many small changes during production. These are roughly dated by the type of brake arm. Although they all look very similar there are dimensional differences that, if mismatched, can cause performance issues. It should also be noted that these hubs come in a variety of finishes including chrome and cad as well as black for the wartime model hubs. The Model D is the most prevalent hub found on American balloon tire bikes.
Model DD 1938-1940? (Two Speed) *a DD kit was offered to convert regular single speed “D” hubs to two speed (“DD”)
1ST Design Model D Brake Arm (1933-1938?)
(little arm “New Departure Model D” with hash marks)
2nd Design Model D Brake Arm (1939-1941?)
(little arm “New Departure” with hash marks)
3rd Design Model D Brake Arm (1941-1949)
(large arm “New Departure” with hash marks)
4th Design Model D Brake Arm (1950-1959)
(large arm “New Departure” no hash marks)
Morrow Hubs
Morrow hubs are dated by a letter/number code on the hub shell. The letter is the code for the year and the number identifies the quarter of the year the hub was produced. For example “H3” would be 3rd (Jul-Sep) quarter of 1938.
A-1931 L-1942
B-1932 M-1943
C-1933 N-1944
D-1934 O-1945
E-1935 P-1946
F-1936 Q-1947
G-1937 R-1948
H-1938 S-1949
I-1939 T-1950
J-1940
K-1941
Musselman Hubs
Musselman hubs are dated on the edge of the shell with a letter and a symbol. The letter represents the year and the symbol represents the quarter of the year. These hubs were probably made until at least the mid ‘50s. Musselman hubs can be found with a variety of brake arms on them. The standard Model M has the arm shown but they can have Airman, Elgin, J.C. Higgins, Western Flyer, or possibly others.