I have two bikes that accomplish about the same thing. The first one is a 81 Centurion Pro-tour, and the second is a gugiefied 71 Witcomb. Both are great bikes. The Pro-tour has been changed to 700c, running flat bar 10 speed, great bike ride smooth runs 32 mm tires easily. It is a half step plus granny in the front, and 10 speed 11x36.
The Witcomb is drop bar 9 speed with bar-end shifting, it is also a half step plus granny in the front, and 9 speed 12x36. It is running 42 mm wide tires on 650b rims.


One thing The Witcomb has over the Pro-tour, is a full custom set of racks and stud mounted Mafac brakes along with two bottle cages. The biggest problem is I have occasional pedal strikes due to low bottom bracket height. This bottom bracket height makes for a very low center of gravity. If I kept the witcomb over the Centurion, I would entertain the thought of changing back to 700c, would require changing the brakes.
Second thing the Pro-tour is completely chrome underneath paint. While it does not have bolt on bottle cages except for one, it can take some good racks which will allow bags to carry any additional water. The 81 pro tours came with stud mounted Centerpull brakes.
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Which would you keep part 2