Right then, time to bite the bullet with all these updates...
Basically, I'll run through the myriad of issues I encountered once the bike was in my possession, and how I've tried to solve at least some of them!
First, the rear brake...
Now, it worked well-enough, and obviously a WTB Rollercam is more-or-less the ideal brake for a bike like this. I was incredibly lucky to have found one, after all. But I'm not going to lie: having a fancy and now ridiculously expensive brake there on the chainstay for a regular daily rider made me more than a little nervous.
I also bought and installed it knowing full-well it'd be going on the Phoenix eventually, as Steve is currently working on a Type II fork for the rebuild, and the brake was intended for that once completed.
There was also a tire clearance issue!
See, the spring for the rollercam sits ever-so-slightly inboard from the brake itself. It's just a few millimeters but that was enough to rub on the already very tight Humptulip tires. And every time I stood on the cranks on a climb, a horrible squeaking noise screamed back at me as the spring met the tire!
Now, the Humptulips are listed as 2.3, but on an older rim they actually measure a fraction under 2.1. Which makes them a great choice for vintage frames. That said, it also means there's next to no alternative option for a modern tire, as most everything else I like is much wider. So it was either run vintage tires, or go for something like the Smoke/Dart repros.
First, I threw on some vintage tires, just to see if something even narrower would help:
It did. But I've learned my lesson with vintage tires: not only are they risky in the first place (these WTB Velociraptors came from another vintage collector and had never been ridden, but even so, the sidewalls had begun to perish in some places), the amount I ride they're just not a viable longterm solution. If I have to track down matching vintage tires every 6-months-to-a-year, I'm going to be bummed out and broke!
The truth is, I really enjoy riding these Renne Herse tires, and I wanted to figure out a way to make that happen on the Merlin, too.
So what I really needed was a rear brake alternative...
I tried a classic XT U-brake first of all, which solved all of the clearance issues:
But I have to be admit, it just didn't do it for me aesthetically for this particular build.
I mean, I like it in these photos, but when I stood back from the bike in the flesh, something just wasn't right. Or not to me, anyway.
That big chunk of black just stood out too much against the rest of the polished parts maybe? And to make matters worse, I just couldn't get it dialed in to perform the way I wanted. Although that obviously says a lot more about me, the mechanic, than the brake itself!
I was telling all this to someone I ride regularly with, who is a very good mechanic in his own right, and he told me he once installed a Paul Racer brake on an older Stumpy with chainstay mounted U-bosses, back at the shop he owns in New York.
Which obviously piqued my interest!
You see, I love Paul Racers! They're one of the coolest brakes around. Just look at it here, on Mark Janikes' custom Potts/Cunningham DIA bike:
Looks good against all that titanium, right?
But here's the thing: Paul's own website says no, absolutely not.
The Racer is not a U-brake, it just won't work. You have to design a bike AROUND IT. The bosses aren't U-bosses, but cantilever, and they have to be placed at exactly the right distances from the rim.
It's right there in the literature.
So I told said mechanic this, and, still, he promised it could be done!
Very fortunately, I have a friend with some Racer's in his parts bin, that he's not currently using, and he lent me a set to play around with, to test this theory:
Now obviously the first issue is these are the center-mount, not braze-on version. Which has an easy enough solution: just remove said center-mount clamp, and jam them loosely on the studs to see how they fit in terms of both clearance and rim placement:
Which all seemed pretty promising...