1981 CB750 Oil tank?
 

Hey there, I've got a quick question that should be pretty obvious. So much so apparently that the answer isn't mentioned anywhere that I've seen.

I'm wondering why there is no oil tank on the 1981 CB750s. I know that the earlier models had it including all of the SOHC models but I don't understand exactly what it was for and why my bike doesn't have one.

Thanks for the help,
--Jonathan