Just changed the oil to 50 weight along with a new filter and went on a 30 mile ride the other day, and noticed when I pulled back into the drive that I had left a trail of oil behind me, coming out of the breather. Never had this problem before..I suspect it's a bad check valve that just randomly decided to go, but if anyone else has any other suggestions, let me know! Is it possible to overfill these things?

Thanks!

 

Wrote this last night but it went away
Yes it can certainly be overfilled...3 quarts is about max on mine.
I leave plenty of room.
As you run it, it should clear it's throat. If not, then something is wrong

 

Thanks race, I put about 3.5 in it which is more than it had before. Also noticed the PO had the vent line and the return oil line reversed. Don't know if this would cause it but we will see how it does now that they're back right again.

 

I doubt those two lines make much difference on a stock tank....
You are running the bike [I mean on a Ride] before checking or Changing oil right??