Hi, cjskach,
There are other things to check, but if I were a betting man, I would bet your clutch switch is upgefucht. It is part number 61 31 1 459 569 and Max's price is $33.66. It is actuated by the clutch lever. You probably can't remove it without cutting the wires and unscrewing it with a deep socket. I think it is 10mm, but don't quote me. First, I would pull the tank and make sure the connections are good. I might also check continuity when the clutch lever is pulled. If there is no continuity, the switch isn't making contact and in my experience, they don't clean well. With the wires cut, you can twist the (bare) ends together and you'll then be able to start in any gear, with OR WITHOUT the clutch being pulled in. To replace the switch, unscrew the old one and screw in the new one. I've replaced 2 of them and only tightened them hand tight, and have had no problems. Once the switch is replaced, plug in the connectors into the wiring harness. Reinstall the tank and you're done. You may be able to get to the connections by just pulling the tank back. I just don't remember. Good Luck!