Yes, lots of old Honda CB750 and old Yamaha Virago types running around south Texas. I think you are right, the old bikes from Japan didn't die they got stuck in the garage or barn and forgotten about. Now they are coming out again. Kid down the street just picked up a V-65 Magna 1984 vintage in perfect shape and runs like a watch for $2800.00.
Funny thing I am noticing is most of the inline fours are shim over bucket dbl overhead cam bikes built 25 years ago. They still run fine. Many in the Harley crowd always think the Japanese bikes are rice burning junk. I have the feeling as many Jap bikes are still road worthy as Harley or Triumph.
Hmmm, I think I know of a new bike out that is shim over bucket and double overhead cam with a chain. Is it possible that you can't really improve on perfection or is it possible that the old technology is just the cheapest way to go?