82 KZ550 No accelleration and knocking noise

I bought my 550 a month ago with 15K miles on it, and naturally, as a new rider, I had no idea that it might leak oil. That is, of course, until it ran out on me. I refilled it with oil immediately after that, and a knocking noise from the cam shaft seems to have started up. I put some Engine restore in it and ran it for a bit, but the problem didn't go away. I also found some metal shavings in the filter when I replaced it. I know this isn't good, but the worst part is, the bike seems to have problems accelerating in 3rd gear. I'm not even sure where to start to diagnose the problem, so any help that could be provided would be excellent.
Thanks in advance.

If you ran out of oil that means that crital parts of the engine were not recieveing proper lubrication for some time.

Basically, you could have widespread damage and might be riding a bomb with a knock like that.

It needs to be completely torn down, and every bearing hand spun to unsure no movement/wear beyond tolerences.

Or just get yourself a new engine that runs fine and swap out the scrap.

Fiddling with the carbs and ignition is NOT where to start, get the engine physically sound first.

GL!