Paul Racer brake finally working!
 

My Bob Jackson was built in 1972 to have fenders over 27" wheels and 32mm tires. So it's a long reach down to a 700C wheel. Originally it had Mafac centerpulls, then for decades Campy Nuovo Record sidepulls with drop bolts (I made the one for the front brake caliper, I think from a rear). The bike never really had great braking but back then what was there to compare to?

A few years back I put Tektro 556 dual pivots on. They were an improvement over the Campys, especially with modern levers and Koolstop pads. But still not great. A couple of years back I put a Paul Racer on the front and put the Campy back on the rear, where braking force matters less. I don't like the Racer and all the degrees of freedom involved in setting it up, but it's a lot more rigid. I had the issue of the straddle cable hanging up in the carrier and the arms not returning fully. Finally I tried a roller carrier (thanks so much to jamesdak for sending me one gratis and fast!) and that solves the straddle cable issue. I rode it all completed yesterday and the bike has the best braking power it's had in all 52 years (almost!) of my riding it.

Roller hangers do make a difference, which one did you end up with? I recently picked up a pair of old Zues 2000 hangers for my travel bike in hopes of enjoying the benefits of rollers without adding to the challenges of disassembly (they are open on the back side).

https://i.ebayimg.com/00/s/NjA2WDc2N..._id=880000500F

What Mafacs were on the bike originally? I'm building up a '76 Eisentraut that came with Campy NR sidepulls and have convinced myself to avoid even trying them. I have a pair of both Mafac Racers and Raids in hopes of running the bike either 700c or 650b with a simple wheel and brake change.