30weight non detergent oil.
I think Jax 184 told you to make sure you have a charged battery in the beastie.. if you run it without one you can blow out a $30.00 Headlight.
also look through
links to manuals there
It is mostly about various expresses, with other suff too.
Listen for several answers and then decide on a course of action.
and FYI between 80 and 81 was the jump to kick start, CDI ignition and auto choke. Don't know which I like better.