I moved your post to the oil section, although, the primary is different for a sporty then a BT model.
Use the search function. Words like "Primary" and "Oil*" (include the little ditty as 3 word requests won't work) and you'll find hours of reading, for your entertainment and lubrication knowledge.
There's been countless threads regarding the "best" oil to use, which is subjective, at best, depending on who you ask.
I usually reply "Baby" only because it's fun to watch them squeeze the babies, to get the oil.
“When the going gets weird, the weird turn professional....” ~ Hunter S. Thompson~
R.I.P. Rubberdown. 1971-2012
"Your Jedi Mind tricks will not work on me...... ~Misinlink-2016~
2005 E.G. Classic
S&S 510 cams
Baisley Oil pump spring
Rinehart 3.5" pipes
S&S adj pushrods
3 stickers (Adding 5 hp each. I swear......)