Originally Posted by
Retro Grouch
If it was my bike, the first thing that I would do would be to measure the distance between the rear dropouts. A modern road bike is 130 mm. I'm betting that your bike is 126 mm.
You'd win that bet. My '85 400 had 126 mm dropouts and came with the same 14x32 6-speed Sun Tour Perfect freewheel this one has.