Technical: Brakes
Dave Hennessey, Stan Diener
K and Sportster Brakes
Harley invented a number of new parts just for the 1952 K-model. Brake shoes, although the same physical size as the Big Twins, were made of aluminum instead of steel. The profile of the “nose” & “heel” of the shoes were different than the Big Twins, and this required different profiles of the pivot stud and operating shaft. The springs, and the attaching points on the shoes, were different from the Big Twins also.
The weight savings of aluminum shoes was minimal, and apparently did not justify the cost of manufacturing and stocking two different shoes and springs. Starting in 1954, the KH used the same brake shoes and springs as did the Big Twins. So a number of parts had to change.
Front - there were three styles of front brakes. The full-width 1964-1969 (and later) front brakes are obvious. But there are internal, and external, differences between the 1952-1953 and the 1954-1963 styles. One obvious external difference - the 1952-1953 side plates had a sand-cast finish. From 1954 to 1963, the side plates were polished.
FRONT | 1952-1953 | 1954-1963 | 1964-1969 |
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Front Brake Side Plate | 44148-52 | 44148-54 | 44148-64 |
Front Brake Pivot Stud | 44156-52 | 44156-54 | 44156-64 |
Front Brake Operating Shaft | 44264-52 | 44264-54 | 44264-64 |
Front Brake Operating Shaft Washer | 6662 | 6663B | 6677B |
Set of Brake Shoes and Linings | 44402-52 | 44401-49A | 41849-64 |
Brake Shoe Spring (2) | 44485-52 | 44484-35 [1] | 41835-57 |
1952 - 1953 | 1954 - 1963 |
Casting number (other side) 44147-52 Note the cut at the bottom right. |
Casting number (other side) 44147-54
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The boss for the operating shaft (foreground)
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The boss for the operating shaft (foreground)
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Operating shaft (left) faces are narrow.
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Operating shaft (left) faces are wide.
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44402-52 Shoes “noses” are tapered.
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44401-49A Shoes “noses” are square.
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Operating Shaft Washers
6662 - 9/16 x 1-1/8 x 3/32
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The 41835-57 spring replaced the 44485-35 spring in later 1957.
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Rear - there were two styles of rear brakes. There are internal differences between the 1952-1953 and the 1954-1963 styles.
REAR | 1952-1953 | 1954-1963 | 1964-1969 |
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Rear Brake Side Plate | 41662-52 | 41662-54 | |
Rear Brake Pivot Stud | 41876-52 | 41876-54 | |
Rear Brake Operating Shaft | 44264-52 | 44624-54 | |
Rear Brake Operating Shaft Washer | 6662 | 6663B | 6677B |
Set of Brake Shoes and Linings | 44402-52 | 44401-49A | |
Brake Shoe Spring (2) | 44485-52 | 44484-35 [1] | 41835-57 |
We don't have any “comparative anatomy” photographs at this time. It is believed that the differences between the 1952-1953 and 1954-1969 styles are similar to the front, except that there are no externally visible differences besides sand-cast finish (1952-1953), and polished (1954-1969). |
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1952 - 1953 | 1954 - 1969 |
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