Tom is correct - the SC always came with good quality Alloy rims.
Three-quarters of the Super Courses in my stable have alloy square drive Shimano/Ultegra or DA cranks, and frankly I don't think it makes much difference, aside from a little weight savings. (And ease of maintenance, if you're unfamiliar with doing cottered cranks, though that problem is resolved with the 1st one you service yourself).
It sort of makes sense to upgrade the DRs' or at least replace the Pulley wheels and shifters if you are running Simplex Prestige.
- I like Suntour Vx luxe, or Shimano Light Action DR's, and Suntour Power Shift DT shifters.
I recently concluded that if you happen to have a Green SC, then a brass bell is mandatory equipment as well.
PS David Newton - $700 is too much for a '73 SC, but the prices for them go all over the map, some going for pennies, and others for several hundred dollars. If you can find a clean one in-between, consider yourself lucky: It will quickly become a favorite ride, no matter what other bikes you have hanging in you garage.
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- Auchen