kirkmears

Hello everyone I've had the bike for many years, but just now really started working on it and able to start it for the first time. I've tried two different carbs, the first one didn't even fit. I had the tank vatted and cleaned and installed a new fuel filter. The carb could be dirty or the petcock is the wrong direction since I don't understand which direction is which . The bike finally started and was running fine for several minutes (5+), then it revved up and hasn't been running right since. Now it's difficult to start, but when it does, it just revs up and dies (<10 seconds). Is this tale-tale signs of an air leak? I am mechanically & electrically inclined, but this is my first time to even mess with a two stroke. The individual that had the bike before me had removed the lights and the bike even started without using the run/stop selector (it's been rigged). Are there online wiring diagrams for these? My best guess is that it's a '79ish model. I did find this link, but my symptoms are just a little different... Thanks for any suggestions!