1984 Chevrolet Cavalier Type 10 "yz80" Questions

What kind and how much oil goes into the gear box on my sons 2000 yz80, just got used with no manual If it was mine I'd start by buying a Haynes manual for it. It's really important to know your toy.

...threaded on both ends does that mean they come out? yz 80 i'm in process of rebuilding a YZ80 motor and one of the cylinder bolts is badly bent it doesn;t want to break loose is there a ...