Those are Shimano integrated brake levers/shifters. I installed Campy Ergo shifters on a 1973 Super Sport. The descriptive (but often despised) nickname for integrated brake levers/shifters is brifter (brake shifter).

http://i32.photobucket.com/albums/d7...IMG5632med.jpg

A dork disc is bad enough on a correct bike, but on a single speed it is even more wrong.

So upon reflection, I have a question. The Schwinn catalog waxes eloquent about how brazing with new special lugs was needed for the oversize tubes, since they were too thin to weld. Just marketing?

Examples
1990 Schwinn 1990 MTB And Road Bicycles -- Foreword
1991 Schwinn 1991 Paramount -- Foreword

Well, there was a lot going on in the late eighties and early nineties with the development of OS tubing so I'm pretty sure there's some substance to Schwinn's claims probably mixed with a little marketing hype.

The 1995 introduction of Reynolds 853 ("the world’s first commercial air-hardening steel for bicycle frame tubes" according to the Reynolds timeline) made TIG welding of thin walled OS tubing practical because the heat from welding actually makes the welded joint stronger in air-hardening steels. But the Tange OS tubing Schwinn used for the TIG-welded PDG Series Paramounts in 1989 and 1990 and jointly developed by Schwinn and Tange was not air-hardening, so was probably designed with thicker butts in the heat affected zone (HAZ) to mitigate warpage from the welding heat.

The heat treated True Temper OS tubing first used in Waterford Paramounts in 1989 was also jointly developed by Schwinn and True Temper and wasn't air-hardening either. Because it was heat treated, overheating during brazing could weaken the tensile strength of the tubing, so in addition to using low temperature silver brazing I'd have to guess the tube butts were appropriately thicker walled to resist warpage and strengthen the tubes at the high stressed joints. I'm not sure what part the development of custom short point lugs played.

http://i32.photobucket.com/albums/d7...ps2d9e3a7e.jpg

similar bike
 

This is a long shot, but incase anyone is still around, I'm new to biking and started riding a bike I've had for a while to commute to my office 11 miles away. I believe it is the same model as the bike as Gunman45. Does anyone have an idea of what is may be worth? I'm picking up renter's insurance and they're asking. Photo of it here:

im gur.c om/gallery/rLB9A80 (new here so has to add a space, apologies for breaking protocol)

I'm aware I've done some out of the norm things to it, but keep in mind I'm 6', 150lbs on a good week, and have not modded the original frame at all. Shimano components with Dura ace cracnks. Only a few nicks here and there on the paint. Serial number is: 2A01885.

This is not the place to ask for an Appraisal. Please start your own thread in our Appraisals forum. https://www.bikeforums.net/classic-v...th-appraisals/

Thread closed