I remember the first 2, maybe three. Wore a couple of each out planning out my Elsinore (which I never was able to get, Dad said I was too big for a 125) and ended up on a 400 in '77, ending the need for hop-up catalogs. GREAT memories for sure!!!
Yamaha MX400B. Dad said I was too big for a 125, we were looking for a 250, and stumbled onto this 400. I really liked the bike, but it would wear me out in 2.5 laps. Holeshot my first race on it, but crashed and got run over in the 2nd turn.