I've been doing some more research. I pulled my engine out recently because it had oil in the mag housing, and I also noticed that a large amount of oil comes out of the PTO cylender when it is cranked with the spark plug removed. The spark plugs look the same, so I don't think it's running lean or rich on one cylender. Problem was the plugs looked fouled after a small amount of use. Like probably 30 minutes of testing and 2 hours of riding. When I initially fired it up after doing fuel system repairs, it smoked my whole shop up. So I know there's oil sitting around in the crankcase(and that initial fire up might have fouled my spark plugs). It sat for 8 years before I got it. After a few minutes of running it stopped smoking excessively. And now after sitting for a week or so it has a slightly higher amount of smoke on startup, and then goes to what I think is normal after a few seconds. I'm wondering what the culprit could be, and why my mag seal has oil in it. I've heard the check valve on the oil pump going bad, and I've heard center crank seals. But my PTO cylender is the one that shoots oil, and my magneto housing is full of oil. My thought process would be if it's leaking from the mag it would leak from the RV chamber, sit in the cylender, and then leak out the outside seal. But theres not a noticeable amount coming out the mag cylinder when I crank the engine over. So it's likely a very slow leak if it's not noticable, and I wanted to know if there's any way to test to see what's the culprit and how fast it happens,, or if I should just reinstall the engine, run it for a while, and open the mag cover a few times to see how bad it leaks. I was wondering if pressure testing both the check valve banjo fitting and the rotary valve oil intake line to 3psi and leak testing them might give me a clue as to where the oil is coming from. I don't want to replace good OEM seals with aftermarket junk, and OEM parts for this thing is expensive. I espicially don't want to replace a possibly good crankshaft with a cheap reman from sbt, as I heard poor reviews of SBT, but I can't go spending excessive amounts of money on a new crankshaft. I want to see if it's only a slow leak that becomes a problem after 8 years or if it's an urgent leak. If it's something that's a super slow leak i'd likely just keep it(and possibly the seals will come back after some use. )
You can always install a valve on the oil feed line. I did that to my wife's ski and no issues except some smoke on start up. 
