> My questions are these: In the 60's/70's was there a trend toward
> larger frames? Are more bicycle enthusiasts traditionally over 6'
> tall? Were shorter frames more likely to be ridden-to-death and
> trashed? Or. . . do you think this is a misperception on my part and
> there really are an equal number of frame sizes available out there if
> you look at the big picture.
It's more like there's been a trend toward smaller frames in the '80s and '90s. Look at older pictures of racers and check out the amount of exposed seatpost compared to what's typical today.
I got my PX-10 from its original owner, who actively raced it in the '60s. He's a few inches shorter than I am. I ride a 54, but the PX-10 is a 56. I still had to raise the seatpost to make it fit me (sort of). Note that it has an 8cm stem, ridiculously short by "modern" standards.
firstname.lastname@example.org (John V. Everett)