Does anyone know what type and how much oil is supposed to go in oil tank and primary of an old 75 iron head sporty??

 

If you have a 75 XLH with a side oil tank. It holds 3 qts. The primary holds 1.5 pints.

I use and most other people will agree straight 50W oil. The only brand of it I can find around here is Valvoline Racing 50W oil. Best oil for it. Us it in the primary and the oil tank.