I guess not all front drum brakes are the same
they look similar, and have a different way of holding the outer drum in place. yesterday I was swapping wheels around on the 125m. I had a 9inch wheel and tire with the brakes attached, since the tire holds air, I thought I'd just use it on the 125. turns out the centerline of the axle to the bottom of the slot that keeps the drum in position is a little farther apart. Even with the locating stud on the axle bottomed out, the axle wont seat all the way in.
I'm pulling it off tonight and hopefully if I remember I'll get a side by side measurement. jim
81 185s
82 185s with 85 200s motor
82 185s
and a 72 ct70