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Primary gasket

There are four different primary gaskets in the 42 years of the K-model and Sportster. This is a testemnet to engineering ethic of Harley, that tried to not make changes for no reason. Indeed, the second gasket can work in earlier application, so you may consider the are only three different gaskets.


Sportster_Engine_Primary_Primary-cover_34955-52A_Primary-gasket_1952-1966 Sportster_Engine_Primary_Primary-cover_34955-52A_Primary-gasket_1952-1966 CAD
This primary cover gasket is for the early aluminum primary covers used on K-models and Sportsters.


Sportster_Engine_Primary_Primary-cover_34952-52_Primary-gasket_1958-1978 Sportster_Engine_Primary_Primary-cover_34952-52_Primary-gasket_1958-1978
This gasket is for the steel primary covers used on XLCH models. It was also used on KR race bikes, hence the -52 model year release.


Sportster_Engine_Primary_Primary-cover_34951-57_Primary-cover_1957-1966_ Sportster_Engine_Primary_Primary-cover_34951-57_Primary-cover_1957-1966_
This gasket is used for the electric-start aluminum primary covers up to 1975.


Sportster_Engine_Primary_Primary-cover_34955-75_Primary-gasket_1976-1990 Sportster_Engine_Primary_Primary-cover_34955-75_Primary-gasket_1976-1990
This gasket is for the new cases in 1977 and later bikes. Image courtesy of those fine folks over at Dennis Kirk, who I hope hate lawyers as much as I do.


Sportster_Engine_Primary_Primary-cover_jewelry_Primary-gasket_1992-whenever.jpg Sportster_Engine_Primary_Primary-cover_jewelry_Primary-gasket_1992-whenever.jpg
I think this is for post-1991 5-speed bikes. It certainly does not belong on an iron Sportster, but here is a picture so you know you got the wrong part.