My original post on top end rebuild was archived so I'll report on what was found on first rebuild. Power valve stop plate was broken off, forcing valve shut, causing rings to wear down cylinder at exhaust port-New Nikasil plating. Type 2 piston w/ rings put in. Reeds were chipped away, went with new Boyseen. Knocking clutch noise came from loose nut on primary gear. Kickstart lever had to be sawed off on knuckle because it was frozen on assembly, in order to get to gears- purchased new lever. Other than that, the bike is tight now. So much compression I can barely kick it over. I have only owned bike since Oct., so the years of neglect can be blamed on previous owner I guess. Can't wait to break in next weekend.