..it says GS650 ..on the side.! Not GSG50? And what's that squiggle after the number? ..never heard of GSG.! ..and a little too big for a 50cc.!! (..i'm not sure about the squiggle ...Jun will enlighten us.! ) just checked ..it's GS650L (1981-82?) Link to "www.sportwheel.com" Doesn't that say GS650SL? It's just on closer inspection that 6 liked more like another G to me. But then I don't know much about bikes.
It's 1981- model. I think correct name is GS650GL though cover emblem says "GS650L". The meaning of "G" is a shaft-drive in '80s, (GS650G,GS650GT,GS850G,GS1000G...etc.)