Motorcycle Repair: clutch, honda cb400t, clutch lever

Question
I have a 1981 Honda CB400T and when I pull the clutch lever to disengage the clutch, while in neutral and the engine running, then press it into first gear, the tire jerks into a spin. Then while still holding the clutch, applying the brake to stop the rear tire stalls the engine. The engine oil is very old and low, and needs replacing. Does my clutch share the engine oil, or does it have its own fluid? How do I adjust the clutch if the problem persists after I change my engine oil? where is the lock nut for the clutch? Also, my bike idles fine, but at higher rpm, it tends to backfire, and when it does the rpm jumps up (while in neutral). Why might it backfire at higher rpm? Finnaly, the engine clanks a bit. I know the oil thats in there is useless, but if it still makes a slight clanking noise after i replace the oil, how do I fix it?

Thanks for your help

Answer
will u please send these questions one at a time?  for the clutch it sounds like your plates have rust on them or need resurfaced.  i suggest a new clutch kit.  your engine oil has nothing 2 do with your clutch as there is now fluid for the clutch.  I would however suggest changing the oil ASAP as old oil will "blow by" your pistons and foul your plugs.  Not good at all and could be the problem causing your backfire.  your noise is either the timing chain or your crank to tranny drive chain.  if its the latter then u may as well ride till u can no longer stand the noise and then buy a new engine.  to much trouble to split japanese engine cases.  if i didn't get all of your questions please send them individually.