Help! I feel like ive seen a thread about oil coming from the cankcase breather, but, when I searched for it tonight it was no where to be seen. So I had trouble with a stripped air mixture screw and I got the old one out and a new one in today so I warmed the bike up and started adjusting ever so slightly and after I turned the mixture screw  and waited about 30 seconds I gave her a little rev to see if there was still some smoke and after I let off the throttle oil shot out of the breather tube, I mean it has some pressure behind it. I only rode the bike a couple hundred miles before winter hit and I make a bobber project out of it so I haven't really rode it much since the rejetting. Does anyone know what causes this? Im at a loss. Thanks!

Sure do/did

I don't know...  but nothing you can do with the air mix will cause that.
It's a separate issue...

Too much oil?...  could the pressure valve in the oil filter have stuck?...

Locating the breather filter higher than the top of the head might help...

Also,.. there is a wad of steel wool located in a pocket at the base of the breather outlet, under the head cover... could that have come dislodged?..

Okay,.. that was a lot of questions and no answers...
Sorry, just thinking out loud... ...

+1 - missing wire mesh

also, where did you get a new air mix screw?

thespot,
  did you ever figure this one out? I actually took my engine completely apart recently and did not find anything that could have caused it on my bike. Wire mesh was in correct location, it had a pretty new filter and oil was at the correct level.