Cable actuated disc brakes are the taint of cycling stoppers. They ain’t traditional calipers, but they ain’t hydraulic discs, either. They are caught in that nether region between the two.
If I didn’t travel with my Seven Cycles Airheart, I wouldn’t have any reason to concern myself with cable-actuated disc brakes. History will judge them to be an evolutionarily unsuccessful branch. The sort of thing that got tried and discarded. And yet. The thing is, I have reason to chase cable-operated discs because I have quick connects for the cables to aid breaking the frame in half (S&S couplers) in order to pack it.
As a result, I’ve tried a number of different brakes. Why? Because if I don’t have powerful stoppers, I get skittish on descents. Stopping power = control.
Ultimately, I kept looking around because nothing was providing the stopping power I need for the descents near my home. Dragging brakes all the way down a descent in order to keep the speed under control is a fun antidote. Talk about things no one needs.
As I checked variations off my list, I finally arrived at the TRP Hy/Rd, their cable-actuated, hydraulic disc brake. Rather than have the reservoir at the lever (where it’s easier to hide the fluid), this places the reservoir at the brake, because cable. So while it doesn’t have the minimal appearance of some of the SRAM or Shimano offerings, it’s a pretty elegant design for what it is. The brake weighs in at 201 grams, which seems like a lot on paper until you remember that this includes the hydraulic reservoir, something that would otherwise be making the lever heavier.
It features a dual piston design with enough fluid to self-adjust as the pads wear.
In setting the Hy/Rd up, I went straight for maximum braking power, largely because the environment in which I ride demands it. I skipped the whole step where I typically use standard brake housing and then upgrade to compressionless housing. Descending around here is just too dicey to set up a bike with anything short of every possible advantage. That said, I did stick with the brake pads spec’d so that my experience would be consistent with other users’. As I was moving from another brake with which I’d been using compressionless housing, my experience of the difference in braking performance was limited to just the brake, not brake and housing.
I went with 160mm rotors front and rear, again, because power.
The upshot is that I finally have sufficient braking power to descend with only one finger on each lever. There’s no question that the power exercised by this brake is inferior to systems like Shimano’s R785 post-mount brake. However, in some very tenuous moments on a recent loose, rocky, off-camber descent, the Hy/Rds gave me the sort of control I just haven’t been able to achieve with non-hydraulic systems. The increase in power has been enough that on occasion I’ve locked up the rear wheel. Sure, I could swap out to a 140mm rotor, but rather than give up power, I’d rather learn just how hard I can pull the lever before I lock up the wheel. Muscle memory is a fascinating aspect of human skill, and I’ve noticed a change in how I brake, one that I can’t quite call conscious.
So, while I’ve made the case for why I still ride cable discs, why bother reviewing them for everyone else, especially if my suggestion at the beginning of the review turns out to be correct and this flavor of brake is as doomed as foie gras?
I am surprised by the number of riders I still see running cable-actuated discs. Though perhaps I shouldn’t be. Asking around, the answer is usually that the ride is some sort of Frankenbike, not a properly spec’d stock offering. For instance, last week I met a guy riding a Specialized Crux, but he’d purchased just the frameset alone, and built it from parts he mostly already owned, save the brakes. Because he was using a traditional road lever, he was forced to pick up a cable-actuated disc. Hey was running TRP’s Spyre and was curious to know how I liked the Hy/Rd by comparison.
I’d have felt bad about slagging on the Spyre if it wasn’t for the fact that I was recommending another TRP product.
I need to take a moment and frame my regard for the Hy/Rd a bit. As I’ve made clear in other pieces here at RKP, I live in Sonoma County, California. The dirt road riding here is flat like the stock market. It’s either on its way up or down. I could ride most of the U.S. and the terrain that makes the Hr/Rd so necessary for me would be utterly absent. Were I still in Memphis, the Spyre would keep me perfectly happy. The Spyre isn’t an inferior product; it’s just not as extreme as we seem to need here.
The Hy/Rd comes in three finishes: silver, black and pewter grey (pictured). Suggested retail is $124.95 for a set; rotors are not included. TRP also just announced a new flat-mount version of the Hy/Rd, which has a somewhat cleaner appearance. Cost and weight are the same as the existing Hr/Rd.
It’s important when setting them up that you don’t attempt to use the barrel adjuster to shorten the throw of the lever. Only use the barrel adjuster to take up cable slack. There is very little arm movement before the reservoir is sealed off, which means that as you brake and wear away the brake pads, the pads won’t readjust and you’ll have to pull the levers deeper and deeper to brake. Also, you’ll encounter brake fade because the fluid will be trapped in the caliper, something that never happened on any of my rides.
Final thought: The later you brake, the more you fun.
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