Metacortex
Wore out three sets of tires already!
Good advice, but it kind of ruins the best looking crankset ever thing. Those guards are what makes it.
i agree, I absolutely love the look (and function) of the chainguard rings on both the Nervar and TA cranksets used by Schwinn on the Sports Tourer. I was disappointed when they removed the outer guard from the crankset on the Superior.
In addition I believe that the inner guard (between the inner and outer chainrings) was not just there for looks but also to act as a ramp to enhance shifting, especially when they were introduced in '71 with 54-36T wide-range rings. However even with the inner ramp ring Schwinn cited shifting problems across that large a gap when it replaced the 36T inner chainrings with 40T rings on the Sports Tourer late in '71.
'71 Sports Tourer TA 54--36T crankset w/inner guard "shift ramp" ring:
'71 Sports Tourer TA 54-36T crankset w/inner guard ring removed (replaced with spacers
These cranksets definitely look bare without the inner guard ring. It is interesting to note that the picture of the Sports Tourer in the 1971 catalog shows it without the inner guard ring. That pic was taken in Sept. 1970 and would have been a prototype built before the inner guard ring had been added.