So I bought a rebuilt '78 a few months ago. It ran pretty smoothly for the first bit, but it was really rich and backfired when you shut it off. Now it seems like it isn't getting enough fuel past second gear. It tries to go, but it stutters and unless you put the clutch in, it dies. This is my first bike and I really don't know where to start. I've taken the spark plugs out and both are oily as well as black on the ends. This leads me to believe it's getting too much gas, but how does that tie into not being able to get past 2nd gear? Any ideas on where to start? Any tips are very much appreciated!