...hehe, lol. If you'd watched it full size it would say: Zündapp. It is a German brand and loved by many older people for it's nostalgia. Some of the parts are still being made, others are sold by people who have a lot in stock, still.
It's a overhauled model from 1971, with some different and additional parts. It's almost as if it was new. The guy spent a lot of time rebuilding it.