Welcome to the wonderful world of Harley Davidson.new here to the harley world .... to my knowledge bike is stock....
I don't mean to insult right off the bat, but you have none. There might be a handful of 30 year-old Harleys that are stock. But you can't tell, just by looking, what is on the inside. Unless you have already been taking things apart and putting them back together.
Whoever you bought it from could have picked it up cheap and just been looking to turn a quick profit. They might not have known any more than you, and could have told you anything to make the sale and you wouldn't know. Your real learning doesn't start until it's your bike.
Is this bike an 883 or a 1200? That could make a difference in your expectations. And did you get any manuals with the bike? The Owner's is pretty important to a first timer, because these bikes aren't like other bikes. A real shop manual could be the best tool you ever buy for the bike, if you plan to do your own work. Or even if you just want to know what makes it work. And a parts manual could tell you if the things you take for granted are factory or not.
Go here to get an online copy of the parts book for your bike. It's not as good as having the real thing in your hands, but pretty close. Just go there and click until you get to your year and model.
Ronnie''s Harley-Davidson''s (onlinemicrofiche.com)
That ought to keep you busy for a while.