I started into this habit of running only one brake on my hillclimb bike. It used to be something I only did for Mt. Washington, since brakes are fairly useless for an event that doesn’t permit you to ride back down the mountain. And why tote that additional 200 grams or so of brake and cable and housing if you’re never going to touch it. Not a completely insignificant savings. So in that regard it made sense.
What didn’t make so much sense, however, was keeping this setup for other mountains. The ones where you actually do get to ride back down. And it didn’t make sense to train with this setup, for example on Kearsarge. I didn’t really put that together until I took my hillclimb rig up there a few times last year. Descending 12%+ grade on a single front brake gives you something to think about. You realize how absolutely super fucked you are if that brake fails!
Brakes have a number of failure modes. Cable can fail. The assembly that retains the cable can fail. Pads, while not particularly likely (it has happened to me once), can fail. The brake itself is held to the bike with a single bolt. That too can fail. Brakes in and of themselves really have no redundancy. Any one of those components fails and the brake fails. Over time, having been exposed to weather, having been wrenched over and over, that becomes increasingly more likely. And given the stresses involved on a single brake that is slowing a 200 pound bike/rider package down the side of a mountain at (x) grade at (x) miles per hour, eh…HENCE WHY BICYCLES HAVE TWO BRAKES.
So I swept these up on the eBay for short money; $115 shipped. TRP 920 SL; lighter than the Dura-Aces and the SRAMs and whatnot, and I read they should perform more than adequately, and I could have spent three times this on something only marginally lighter. So I suppose I’ll keep both of them on, and descend in relative safety from hereon in.