Doesnt sound too healthy - first things first. Are you running enough octane in your fuel? 91 minimum. Correct spark plug BR8ES? Compression test? If all is well with compression do a leakdown test. If all is well with a leakdown start checking ignition components - wiring, TORS system (if still on) - make sure your stator plate has not been modded (timing advance), all stator components are tight and in place - test them all with a DMM. Too much timing or a faulty ignition system can cause detonation (spark knock)
If you do not find an internal engine issue its time to look at fuel delivery - make sure you line is clean and producing a good stream of fuel when the petcock is on. Check your intake boot for cracks and leaks (leakdown should show these if present). Check your reeds, if they are broken or not sealing the unit will NEVER run right. If all is well with the fuel system its time to check into your carb. A good thorough cleaning will be helpful.
Delete that oil injection system, they fail too often and are unreliable. Use a block off plate, plug the carb port and just mix your fuel in the tank. This will save alot of headache.