Panhead front brakes 1948-1949 springer
This front brake assembly is used on big twin Springer front forks 1937-1949
There are two types of brake drum that will fit this brake assembly. a pressed steel drum 1937-1939
and a cast steel drum 1941 and later.
1937-1939 and 1941 and later backing plates are interchangeable.
The “Glide front brake” is used on hydra-glide, Duo-glide and Electra-glide 1949-1971
1949-1968 glide front brakes are mounted on the left slider.
1969-1971 brakes are mounted on right slider.
Drums backing plates and shoes are year specific.
Early drum 1949-1966
later drum 1967-1971 to accommodate new wheel hub.
Early 1949-1968. late 1969-1971 to accommodate right side mounting.
Early shoes are longer.
This mechanical rear brake assembly is used on all big twins 1938-1957.
Drums are made of stamped steel.
Upper and lower shoes must not be interchanged 1938-1957.
In 1958 hydraulically actuated rear brakes were introduced.
Drums and sprockets
Early 1958 drums are stamped steel with 1/8″ rivet holes. 1-5/64 shoe. Same as mechanical brake.
late 1958-1959 are cast steel with 1/8 rivet holes.1-5/16 shoe.
1960-1962 cast steel with 3/16 rivet holes. 1-5/16 shoe
1963-1966 cast steel with 3/16 rivet holes. 1-13/16 shoe
1967-1972 uses drum designed for the later hub.
Backing plates, sprockets and many other components are drum year specific.
This rear brake master cylinder is used from 1958-1972.
Here are some great resources for more detailed information about Harley Davidson Panhead brakes.