I just started reading up on the old Schwinn road bikes. I know the fillet brazed bikes ie Superior, super sport, and sports tourer are all all Chicago made. But what about all the other "light weight" and x-tra lite Schwinn's like Continental II, Varsity Suburban, Collegiate Sportabout, Runabout Calient and Traveler (sport), Le Tour ll (sport) Superior (sport). Is there a difference between a Superior and a Superior (sport)? Another question I have, how easy is it to replace the original cranks with newer cotterless cranks?