First, Ashtabulas have some virtues. The large bearing rings give LOTS of support. The "inside-out" configuration is easy to use, and easy to adjust, once you figure out that the lock nut is left-handed. They probably survive non-maintenance better than the contemporary alternatives. What I really liked, though, was that you could get short cranks really cheap, for things like kid-back Schwinn tandems.
Second, the pitch: As part of a purchase of an off-topic tandem a few weeks ago, I had to take the rest of the bikes (including an Alenax), and got to take whatever old parts I wanted. This included a few Ashtabula-to-cottered crank conversion crank kits to make your Schwinn Superior or Super Sport a really hot item. Think of the looks you'll get with a Williams or Magistroni or Simplex or Duprat crank on them (depending on which national standard they turn out to be). :-) Since the list rules say I have to put a price on them, I'll say $40 each. Not that I expect to get that, but it just assures that if anyone wants one, I'll see exactly what they are.
mcLean va usa.
>>>> The other problem with a one-piece alloy or Ti crank is figuring
>>>> out how to
>>>> get steel bearing races on the spindle.
Ashtabula cranks have races that thread on to the "spindle" after the arms are directed through the BB. They are opposite of standard BBs in that the bearing cups are on the inside and the races are on the outside. So, steel cups and races could be used on arms made from any material. If I recall, in the early BMX days, there were some pretty fancy one-piece crank arms that featured hollow cro-mo arms welded to the spindle. The racers our shop sponsored back then favored these over the alloy three-piece BB setup because they would trash the alloy square-taper arms in no time at all.