Needless to say the part that broke was the carbon outer plate. Not the alu knuckles, plastic pulley wheels, ti and alu bolts, or even the steel pivots. The carbon bit!

So I was a bit pissed, and replaced it with a decade+ old all aluminum campy Athena 8-speed mech, which worked perfectly with the 10-speed Centaur cassette and Record shifter, btw. I looked into replacing the plate, which was $150, and decided I’d be better off buying a used Record or Chorus mech anyway. After chasing a few of those around the Czech internets for a week or two, I gave up and settled for the old alu bit.

But after a couple of months of seeing this broken expensive piece of shit in my apartment, I decided to take some action. So I ground-up/filed-off some mixed length (0.5-10mm) fibers from the cutoff from a carbon cross fork, and went to work laying it up.

The knuckle has a brass(?) sleeve pressed into the carbon on either end, and a steel pivot rotates inside each sleeve. The sleeve is what broke out of the carbon, so I figured I’d put it back. With some good Czech epoxy and the carbon fibers and a little patience (luckily as that was all I had to spare), I had built up a nice reinforced gusset on the forward sleeve and realigned/repaired the contact points for the sleeve. It took a bit of twisting and prying to get it all back together even though it was 99% aligned, but it seems to be working now, so we’ll see.

repaired record outer knuckle

In the end I was pretty happy with how the carbon came together. A very little bit of finishing work with a small file, so I have a reasonable amount of faith in its durability. But don’t think I’ll be repairing any handlebars anytime soon though.