Hey All I have '82 with 70K miles. After sitting for a few years got it up and running. 1st ride about 5 miles motor started making knock from front head area. Zero compression from front great compression rear. IDEAS?!?!?!
First guess would be a stuck or bent valve. pull the cam cover and check valve clearance.
Disfunctional cam chain tensioner? Could be the chain 'slipped' a couple teeth on the cam. Walt is correct, remove the cam cover and check valve clearances, and look around in there for any clues.
So Rick, what have you found?