The HD part number is (34951-52) and the casting number is (34950-52).
Gasket: (34955-52).
Fasteners: (3) cover screws and no dowel pins. Case has pin bosses but they are not drilled out.
The original cover finish is natural (as cast).
Cover has a divot in the lower bottom to clear the sidestand mount.
There is an oil level plug boss behind the divot but the boss was not drilled and tapped for a screw.
Rear brake switch boss on the rear of cover.
Oil filler plug (34742-52) screws into the cover. It has a small hole through the center to vent the primary compartment.

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The HD part number is (34951-54) and the casting number is (34950-52A).
Gasket: (34955-52A).
Fasteners: (3) cover screws, (4) 3/16“ dia roll pins to locate the cover to the case.
The oil level plug boss was moved in front of the lower cover divot, hole was tapped for a screw (3728) and a washer (6218W).
Half moon divot added to lower rear near brake switch boss to clear brake lever return spring.
Rear brake switch boss on the rear of cover.
Oil filler plug (34742-52) screws into the cover. It has a small hole through the center to vent the primary compartment.

Click on a pic to enlarge: ⁵⁾

The first primary cover for Sportsters. Cast aluminum with the “Sportster” script cast into it.
It was replaced in 1967 when the electric start was added to the H model.
It is similar to the K-Model (also KH and KHK) primary which preceded it, with two notable differences.
The K-Model primary didn't have the scrips and the Sportster primary protrudes out further accommodating the compensating spring on the motor sprocket. ⁶⁾
HD part number is (34951-57) and the casting number is (34950-57).

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Click on a pic to enlarge: ⁸⁾

The XLCH primary “tin” cover has several versions. Below are the two used on production models from 1958-1969. ⁹⁾
There are no casting numbers on these covers as they are stamped steel.
The 1958-1963 version is very similar to the 1964-1969 version. The only difference can be seen from the back.
Notice that the inside of the derby on the 1958-1963 version is smooth because of the two-piece construction.
The '58-'63 XLCH primary covers are sometimes referred to as “double derbies”.
Click on a pic below to enlarge:
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HD part number is (34949-58) and it's made of stamped steel.

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HD part number is (34949-64) and it's made of stamped and chromed steel.

Click on a pic below to enlarge: ¹²⁾

The HD part number is (34947-67) and the casting number is (34950-67).
This is the first electric start chain cover.
The hump-back on the rear of the cover mates up to the hump on the left case where the starter is mounted.
The boss near the hump holds a Torrington B1210 bearing (9063) for the starter shaft.
The tiny hole below front mounting bolt on the hump (as installed) is for a locating pin to the case for bearing alignment.

Click on a pic to enlarge: ¹³⁾

Click on a pic to enlarge. ¹⁴⁾

Click on a pic to enlarge: ¹⁵⁾

Click on a pic to enlarge: ¹⁶⁾

Click on a pic to enlarge: ¹⁷⁾