See also in the Sportsterpedia;
….. *57-85 Oil Line Routing
….. *Pics and Information on stock IH Battery Trays and Parts

Click on any pic below to enlarge:

Click on a pic to enlarge:

The oil filler tube is on top of the tank under the seat and there is a sight tube to check the oil level on the left side of the tank, front corner.
With the motorcycle on upright, there will be 1/8“ of air space at the top of the tube when the oil tank is full (3 quarts).
With the bike on the jiffy stand, the tube will be full (no air space) when the tank is full.
With the bike on the stand and the tank with only 2 quarts, there should be a 1-1/8” air space in the tube.

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