Nice 143 Max. Actually, it is a late 143 produced about 1976. The first model came out in 1975 and did not have the sidestand or tabs for them on the swingarm, only had a centerstand. Also the early ones had the larger tank with tool box and fiberglass fenders. I had one of each, bought the early model one in 1975 when it was new, and they are great bikes.
My 143 in my pix was a late model and I got an early model tank for it when I was restoring it. Many of the late 143's with the sidestand tab had damaged swingarms after years of idiots trying to start the bikes while standing on them with the sidestand down. That would eventually rip the metal tab out of the swingarm. I was fortunate to find a new original swingarm from a dealer in Canada when I restored my late model 143.