1. Decomp valve that is notorious for leaking. Aaron is correct that it is supposed to make turning the engine over easier. Its really unnecessary on a Sachs. Common on belt driven mopeds. Replace it with a bolt. Seriously, it is only a future problem if you can even find a decent replacement.
2. Bosch ht (high-tension) coil. If you have spark, it's working. That's a quality part that rarely is the culprit.(edited)