The end result of the conversion of James' 1983 Schwinn Super Sport from a Campagnolo-equipped road machine to a Shimano gravel bike looks great and operates smoothly. However, trying to work with the new GRX 1x10 group was unnecessarily problematic, despite the research that I put into assembling the bike.
There were a couple modifications that had to be made to the bike and our overall plan, but we knew beforehand that this might be the case. We realized that clearance for the knobby tires and the reach of standard road brake calipers to the rim's braking surface might be an issue. Ordering a set of brakes with a longer reach solved both of those problems.
The vintage Schwinn had brake mounts for older, flush-nutted calipers, instead of the modern recessed mounts. I had no problem drilling out the back of the fork to accept a recessed nut, since there is a thick wall of steel in that location, but I didn't want to drill out the delicate rear brake bridge. We got around this by purchasing two front brake calipers, which have a longer mounting bolt, and attaching the rear brake with a nut and concave washer.
Despite having read from a couple online sources that 10-speed Shimano 105 (or Ultegra or Dura-Ace) shifters will work with a GRX 10-speed derailleur, they do not. The cable pull in the levers is not adequate to extend the derailleur to the largest cog - many of the other nine gears were operating noisily, too. The funny thing was, I had purchased a 105 long cage derailleur from an employee at a local shop, as part of a set with the shifters. I didn't think the derailleur would have the capacity to shift to the 34-tooth cog on the cassette, but I threw it on out of desperation, and it works perfectly!
I've learned to handle compatibility issues with patience, but it is annoying when the "expert advice" steers you wrong! That said, this bike should encourage anyone with an old bike in their garage to upgrade to modern parts and make it perform like it's a new machine.
I don't have much else to share this time around, but I was able to complete the stripping, repaint and application of new decals on a Concorde Aquila frameset in PDM team colors. I also painted in the logo engravings on the fork crown.
First race of the "Classics Season" is tomorrow - Omloop Het Nieuwsblad!
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