Primary Case Oil

Primary oil, oil for the primary housing

Due to their design, Harley-Davidson motorcycles require extra lubrication for the primary drive, i.e. the connection between the crankshaft and clutch. While the older models relied on drip lubrication, the smaller V-twins (K models, Sportster) from the 1950s onwards and the Big Twins with the introduction of the 5-speed gearbox had closed and oil-filled housings for the primary chain, which from then on ran in an oil bath. Like all other oils, this oil filling must be changed regularly.

Our PanAm oils are carefully matched to their intended use and are of the highest quality.

How often do I need to change the primary oil?

This is model-specific and we refer you to the manuals. For the K and Sportster models, it should be noted that the gearbox and primary drive have a common oil filling and until the end of the 1970s the same oil was filled here as in the engine oil tank.

The filling quantities and oils required for a primary oil change can be found in our Tech Tips or, of course, in the manuals.