TRP cable actuated hydraulic disc brake caliper and master cylinder

TRP has just shown two new disc brake calipers, and both are quite exciting and interesting. Above is the Hy/Rd, a cable actuated hydraulic disc brake caliper. The hybrid design lets you run standard cables all the way from the lever to the brake, which should make installation on internally routed frames a cinch while still (theoretically) providing the power and modulation of a hydraulic brake. And if you’re already running mechanical discs, it’s pretty much a drop ‘n’ swap operation.

It works by putting the master cylinder directly on the caliper body, letting the cable pull a lever connected to the plunger. We really like the inline barrel adjuster, too. Overall, it looks like a much more user friendly option compared to their Parabox while still letting you run whichever drivetrain group you currently have.

More details on this, plus a dual-pull mechanical caliper, below…

TRP Hyro cable actuated hydraulic disc brake caliper and master cylinder

One particularly interesting feature is the knob/button on the top – it appears to be a push-lock type button, presumably to prevent the brakes from being activated while the wheel is removed. If so, it’s a brilliant little safety measure.

UPDATE: Here’s what that button really does, per TRP’s PR man Lance Larrabee: “The lock is designed to hold the lever arm in place while you tension the cable to make certain the lever arm can fully return so that the oil can refill in front of piston.” Presumably, you could also use it to keep the pads from squeezing in, as was our original assumption.

Colors look to be matte black and polished silver. One concern we have is heat build up since the master cylinder is directly next to the caliper, which means no extra fluid volume or hose length to help dissipate heat. For cyclocross or commuter bikes, shouldn’t be a problem, and if it works with cable pull ratios for both drop and flat bar levers, they could have a winner on their hands. TRP’s being fairly mum on specifics for now, the official launch is at Sea Otter but we’re trying to line up a test pair before hand.

TRP Spyre mechanical dual pull disc brake calipers for road and cyclocross bikes

Perhaps just as exciting is the new Spyre dual pull mechanical disc brake. Using a lever that rotates around bolts on both sides of the caliper and pushes both pads simultaneously and evenly, we expect it’ll have smooth action and a comparatively powerful feel.

TRP Spyre mechanical dual pull disc brake calipers for road and cyclocross bikes

Presumably this is also aimed at the road/cyclocross crowd, meaning the leverage ratio might be designed around a drop bar lever’s cable pull. For the uninitiated, having both pads move inward means easier set up and the ability to have a little more space between the pads and rotor when unengaged. It also means one pad isn’t bending the rotor as it pushes it into the static pad like on current calipers like Avid BB7 and Hayes CX5, among others.

TRP Spyre mechanical dual pull disc brake calipers for road and cyclocross bikes

Perhaps the best part about this one is that they’ve managed to double the movement while making one of the smallest, sleekest mech calipers we’ve seen!

The design of both this and the Hyro mean pads are bottom loading, which requires wheel removal, but really, how often are you changing pads?

TRP Revox carbon fiber and alloy cantilever cyclocross brakes

If all this talk of disc brakes on your ‘cross rig is heresy, TRP’s still developing their high end cantilever brake line, too. The latest Revox are offered in carbon fiber and alloy and were introduced at Eurobike.

All photos courtesy of the fine folks at, who are covering plenty more new stuff at Core Bike this week. Check their first round up post here!


  1. I love these designs. I’m kind of curious how massive the hydro caliper will look mounted to a bike. But the setup looks like a much better middle point to full hydro than the Parabox is. The wheel change lockout (if that’s what it ends of being) is a great feature.

  2. Shades of Mountain Cycle Pro Stop discs from 1991. Mechanical cable pull over hydraulic. Worked well but tended to need a regular bleed.

  3. Interested to see the weights for the Spyre. In addition to looking great, I would hope it also has a weight advantage over the two previous dual pull offerings, the IRD Dual Banger and the Gusset Chute.

  4. Shades of the Amp Research brakes from the 90s. Hopefully that reservoir mitigates some of the explodier characteristics of those previous offerings.

  5. Totally didn’t expect or even think of that. Kinda mind blowing actually, almost want to buy one and run it on my CX bike in place of Avids just to see what it feels like.

  6. With decent housings and cables, I doubt there would be a worthwhile difference in performance between the Spyre and hydraulics for road applications. Plus you won’t have as many worries about heat and the superior pad retraction should eliminate noise issues for slightly out of true rotors.

  7. Er, why? Isn’t the main advantage of hydo doing away with the cable? No stretch, no sticky cables, no maintenance. Seems like the worst of both worlds?
    The Spyre looks great though, could be a great upgrade over a BB7. Hope they do a mountain pull version as i run flat bars on the commuter bike.

  8. As the owner of some crappy BB5 clones on my Norco CCX2, I’d buy these just for the pleasure of not having to adjust the pads constantly. But I’ll probably go with the Hope V-Twin or TRP Parabox instead, as my cables are external.

  9. With the rotor speeds being higher (rpm) than on dirt, I’d imagine there’d would be a larger initial heat buildup. I wonder how a system with so little fluid (compared to full hydro) will deal.

  10. I really like Tektro. Solid engineering and build quality at affordable prices, and now this looks to be quite innovative in a market that hasn’t leapt ahead quite as quickly as most people expected it would.

  11. @paulpalf: one advantage of such setup over BB7 is that both pads move, not only one. It does improve modulation and power. You can also use disks with steel braking surface over a stiff aluminum career. Those do not work well with mechanical. Tried to run Shimano icetech’s with BB7 on my single speed – ended up buying some cheap hydraulics Deore’s (which are $80 for a pair, and work better than previous generation XTR (which was without servo wave cam)

  12. I find the hydro/mech to be a little counter intuitive. As mentioned before, the low fluid volume would be more prone to overheating, and the rider is likely to experience issues that are similar to cable actuated brakes i.e. cable stretch/ housing compression, contamination, and modulation issues. The dual actuation mech brake is a good step forward. It would give a more even engagement with the rotor and should improve modulation. The key to both of these systems would be running a Nokon/ Aztec hard housing system. The benefit of this system is that it eliminates housing compression and allows the ability to run full liner. This would keep the system cleaner and working properly longer.

  13. The dual mech is intriguing, especially if it self adjusts, but having the reservoir for a hydraulic brake built into the caliper strikes me as a major no-no. Just like ti struck anyone who rolled the Hayes or Mt Cycle/Rock Shox brakes abck in the day.

  14. Avid caught napping for sure. Both designs look great. Mechanical discs still have a lot of potential. Simpler design, lower weight. The master cylinder just adds a lot more mass to what should be a simple design. To me the Hy/Rd is a transitional design. Compressionless brake housing can be a big improvement for cable-actuauted brakes.

  15. While both designs should increase pad clearance, the Hy/Rd is (presumably) self-adjusting, which seems to be the killer app for its design. While burning through pads in a particularly muddy cx race is a possibility, the issues people were having at nats in wisconsin will be reduced, since the pads (again, presumably) move closer to the rotor as they wear. While I cannot think of a disc brake that is not self adjusting, the P5’s hydraulic rim brakes are not, so this is an assumption that isn’t confirmed by the article

  16. I am a huge fan of the mechanical caliper with the dual piston design. This idea has been a long time coming. I hope our friends at Shimano and Sram are watching this closely. As for the hybrid design the heat management is highly Suspect, yet you can’t ignore the persistence of these guys. I remember dealing with the Hayes and amp research versions of these back in the 90’s. I was glad to see this design disappear back then. I have heard that Shimano is very close to brining their di2 / hydro to market. This should offer a XT type caliper. This will be the design to beat.

  17. i don’t even like bikes anymore and i’m excited about these. i’m sure trp’s r&d teams work very hard to minimize the problems that many of you resplendent bicycle sages immediately assume they will have based on your extensive experience with and deep understanding of antiquated systems that did not live up to your completely reasonable perfectionist standards.

    that said, they will undoubtedly fail.

What do you think?