need some help about the clear thingy on the oil tank

cuz most people get oil blockoffs if they race, so they can burn leaner, to go faster, but anyway...if you are talking about the clear window for the oil check thing...you should see oil in there, cuz...that is your MOTOR oil...not your mixing oil, that would be that "Sae 10W 30" or Yamalube4...etc, but, you should see it half way up that clear piece (that is if i am not mistaken)