The ZA7S....numbers are in the registration certificate. The YA7.. numbers aren't visible in documents. Never mind at the moment.
However, Swarfcut, you told about, I should check the number of teeth on the rear sprocket. This was another very useful informaton. I counted 49 teeth. So, it is problem for me, I need a standard sprocket with 46 teeth, and a new chain. Maybe could you offer a helpful website to buy?
On the other hand, the first gear crunch a little bit. But awful if I change from two to one.
So I must adjust to the clutch, but I feel a little clearence at the arm, not too big in my oppinion, maybe I must check the cluch springs pressure.
I will not get bored.