Ok this one is just for the WTF factor. Some may have noticed my other post "anyone need xs500 parts" where I describe my parting out of a yamaha xs500 that apparently had no compression. I got this bike for free, the title situation is bad because the PO that gave it to PO that gave me the bike
signed and dated it 1996. In other words the guy I got it from never transfered the title to his name. Whatever. The bike leaked oil like hell from the alternator cover and between the oil filter and its housing when turned over, plus it had no compression so I figure hell, part it out on ebay, make a couple bucks. Now I never did the formal compression test by hooking up a guage..didnt seem to be a reason to. I could turn this thing over by pumping the kick starter with my hand using minimal force. I also tested it by putting the bike in gear and pushing it with the clutch out and there was only slight resistance. The plugs where in it and tight. So in my mind theres only three things that would cause this: bad rings, hole in the piston, or stuck valves/timing way the hell off. I assumed that since It came to me with such a terrible oil leak(I mean it was pouring out when you turned it over with the starter) that the PO ran it out of oil and killed the rings that way. So I'm tearing down this motor, valve cover comes off, valves look great from up top and the cam chain has good tension. Break the cam chain and head comes off, flip it over, yep valves are fully seated, look great. Now I get a look at the cylinder walls. Push each piston down so I can see and feel inside, smooth as can be! Pull the clyinder block and the pistons look great and the rings look ok too!??? Can someone tell me what the hell I missed? Its no big deal cuz I got it for free, its completely torn down now and partially sold on ebay. But damnit, this was a cool bike, almost all there and in great shape with 18k on it. Did I make a big mistake by making assumptions?