If you haven’t noticed by now, road discs are coming. The benefits of a road disc brake system have long been understood, but designing a system that functions in the unique circumstances of high performance road cycling has proven harder than anticipated. With hybrid offerings leaving something to be desired, improved purpose-built road disc brake systems have become a target of many industry leaders.
Looking to capitalize on the new wave of road stoppers, TRP -the high end division of Tektro- has been at the forefront of road discs starting with their Parabox Hydraulic disc brake converter. Even as hydraulic integrated shift levers are popping up, the truth is that there are still an incredible number of mechanical brake levers both out in the wild and on lower end bikes, so designing a disc brake that’s compatible with them represents a huge opportunity for both OEM and aftermarket.
Not content to just create a better hydraulic brake, TRP thought they could reinvent the mechanical disc as well, resulting in the TRP Spyre mechanical and HyRd mechanical/hydraulic road disc brakes. The brakes have been teased for some time, though we finally got to put some real world testing in the hills of Los Gatos on both braking systems to see how well they could take the heat.
Read on for first impressions and tech break down of the HyRd and Spyre…
You may not think of TRP or Tektro as a leader in the world of brakes. But with 1,400 employees and 4 factories in both Taiwan and China, with a US office in Ogden, UT, the company is much bigger than you might expect. The Tektro brand is nearly ubiquitous on many less expensive bikes, and over the past few years TRP has been growing their share of the high end brake market.
Three years ago, TRP introduced the Parabox, which while functional when set up properly, it wasn’t the most user friendly brake system on the market. The whole point of the Parabox was to act as a mechanical interface between standard shifters and hydraulic brakes and did so with a hydraulic master cylinder “box” that attached under the stem. However, that led to stack height issues, shipping head aches, and complicated set up which led TRP back to the drawing board.
The result? The all new, TRP HyRd mechanical/hydraulic brake. Building the entire master cylinder and reservoir assembly into the caliper, the HyRd side steps the issues of the Parabox and offers hydraulic performance with mechanical simplicity. The design makes it unnecessary to bleed them even with installation on an internally routed frame, makes boxing a bike for shipping simple, and frees up valuable real estate on the steerer for your stem. On paper, the only negative of the HyRd is the size of the caliper, which is quite a bit larger than a traditional caliper – mechanical or hydraulic. The size of the caliper is certainly something you won’t notice while riding the bike, though hanging the bike on your wall is another story.
Inside the HyRd, the internals function just like a normal hydraulic brake would, only the reservoir is directly on top of the caliper without the hose connecting them. In the case of the HyRd, the “brake lever” is replaced by the cable anchor which then activates the master cylinder pushing the piston past the timing port and then pushing fluid to the caliper pistons. Click image to enlarge for detail.
- 195g per wheel, 89g rotor 160
- $150 per wheel rotor and adapter,
- Polished body with black anodized cap -or- black anodized body/ with polished cap
- Open hydraulic system – adjust per wear
- Compatible with all shift levers
- Composite pistons, 21mm Bakelite plastic – excellent for insulating the brake fluid from the heat
- 160 kit, or 140 kit, 2 adapters included for use with front or rear
Spyre Mechanical Disc Brake
Mechanical disc brakes are simple, reliable, and easy to work on – but they’re also usually noisy and don’t offer the modulation and power offered by their hydraulic cousins. To address this, TRP sought to perfect the dual-piston mechanical design which if done properly will always be superior to single piston brakes. While TRP wasn’t the first company to create a dual piston mechanical (IRD has had theirs out for years), TRP certainly cleaned up the design with a sculpted hoop that replaces the standard lever arm. The design of the hoop is critical as it allows for actuation of the brake without a wide lever arm sticking out where it can strike your heel – very important as road bikes transition to the 135mm rear spacing. The hoop is available in aluminum for the standard model, and will be offered in the lighter SLC version with a carbon lever arm.
Using a similar ball bearing movement as other brakes, pulling the lever causes the ball bearing plates to rotate on the ball bearings pushing the pistons and brake pads into the rotor. With dual pistons, the movement is equal on both sides applying equal pressure and increased power compared to single piston brakes. A massive spring in addition the to brake pad spring resides in the center of the caliper which serves to push both pistons back into place after the lever is let go. Slide a small Torx wrench through the inside pivot and you can adjust the starting position of one side, letting you dial down the total amount of space between the pads and the caliper.
Both the HYRD and the Spyre use brake pads that are the same size and shape as the prevalent Shimano M515 brake pads so replacement pads will be easier to source in a pinch.
- Ball bearings, dual piston movement
- SLC–carbon lever arm version and standard aluminum arm version will be offered
- $80 per wheel, $110 SLC
- 148g SLC/154g Standard – 40g less than bb7, 20mm narrow, ~20% more claimed power
- Ramped ball bearings, with barrel adjuster and single sided pad adjustment
- TRP brake pads – semi metallic, Shimano compatible for many size options
As one of the biggest concerns with hydraulic or mechanical road disc brakes is heat management, TRP devised a series of tests to push the HYRD and the Spyre to their limits and then some. In the switchback test, brakes are cycled on and off in 10 second intervals for 88 cycles with 6kg of lever force at 25kph. Testing resulted in an average of 761 watts with a peak in excess of 1000 watts causing the rotor to heat to over 900 degrees f. At these temperatures, the paint on the backing of the brake pads would flake off, but the brakes continued to function.
The second test was termed the scared rider test which involved 10 minutes of continuous lever pull at 3kg of force with the wheel again traveling at 25 kph. This is to simulate exactly what it sounds like – a rider terrified of a steep descent, dragging the brake the whole way down. Again, both brakes passed their testing according to TRP who was quick to point out that the testing did not include the air cooling effect of riding the brakes in normal conditions – as the ambient air rushing over the calipers and rotors would further cool the brakes.
While they wouldn’t say who, TRP mentioned that they purchase their mineral oil from the same source as another famous brake manufacturer, we think you can figure it out. Likewise, TRP pointed out that at those extreme temperatures, glazing of the pads becomes a much bigger issue than the fluid itself boiling. TRP hasn’t set a weight limit on the brakes yet, but they are currently testing both brakes with tandems to guarantee they are adequate. When asked about rotor size, TRP recommended that road riders always use a 160mm rotor in front, but can get away with a 140mm in the rear. In cyclocross-only applications, you should be fine with two 140s.
In order to truly get a feel for the new brakes, both Tyler and I were invited out to Los Gatos, CA, to ride both brake systems in the surrounding mountains. Essentially, the ride was to find a really steep hill, climb up it, and then ride down like hell. The tight, twisty, technical descents the surrounding hills had to offer were a great test of braking performance and more importantly, heat management as we purposely dragged, panic stopped, and scrubbed our way down the mountain to try and make the brakes fail.
Coming from my time with Volagi (which happened to be one of the test bikes today, for disclosure) I was in the unique situation of having spent a lot of time on an identical bike with different disc brake set ups. My first ride of the day was on a Viaje equipped with HYRDs hooked up to Dura Ace 7900 levers, which initially jumped out as being one of the smoothest braking road disc setups I’ve ridden.
Honestly, the design of the HyRd initially struck me as clunky and the fact that they still have a full length cable and housing left me secretly hoping they would be terrible, but the exact opposite turned out to be true. Extremely smooth, with great modulation and most importantly – quiet. Thanks to the open hydraulic system that automatically adjusts for pad wear and maintains consistent air gap, the rotor never rubbed on the pads – essential for use on the road where noises aren’t masked like a mountain bike. Even under extremely aggressive braking or dragging, my bike left me concentrating on the road not the brakes with easy to manage power the whole way down.
One thing is for sure, if I had the choice between other mechanical to hydraulic brake systems out there and the HyRds, the latter would win out for sure. I’m assuming a dedicated hydraulic brake/shifter lever will be superior, but for those who already have mechanical brake/shifters the HyRds seem like a worthy upgrade.
When it came time to try out the Spyre, the switch clearly illustrated the benefits to the HyRd’s set up over the Parabox, with Martin, Dave, and Lance switching out brakes on the side of the road. Just to be clear, no one would ever attempt to install a Parabox on the side of the road, let alone an entire fleet of bikes for a bunch of bike media guys. Soon, the brakes were switched and we were off riding again.
When it came to the Spyre mechanical brakes, my initial reaction was not quite as favorable as the HyRds, but probably only because the HyRds were so impressive. The Spyre (also set up on my bike with Dura Ace 7900 levers) offered good power, with decent modulation. The feeling at the lever isn’t as crisp as a really well set up Avid BB7, but when you factor in the power, the lack of noise, and the heel clearance the Spyre has to offer, justifying the BB7 is a tall order. My bike set up with the Spyres had zero issues with fade, and even after really hard braking, were quiet and drag free.
Overall, it seems like TRP has two killer brakes that address the potential issues of road discs. We want to get our hands on some long term samples to confirm, but my initial impressions were definitely confidence inspiring.
My test bike for the HyRD was the Foundry Ratchet, whose brake cable routing was designed with other brakes in mind. The frame’s cable exit port and the HyRD’s entry point caused a dramatic kink in the housing directly before the ferrule went into the caliper. The result was too much cable drag and a bit of a “soft” feel for the back brake. The front brake, however, felt almost as firm and grabby as a standard hydraulic brake system. I rode around the parking lot on a different size Foundry and on a Volagi Liscio with HyRD and their rear brakes felt much better. So, my hunch is it had more do with the layout than the brakes. We were also testing with a 160mm front rotor and 140mm rear, which would bias power toward the front. General braking power was good on the front and mediocre on the rear for my particular set up.
I started this test ride with a few full stops from high speed, and during the extended descent there was no fade in performance. Having tried two other bikes that felt really good on the rear, I’d like to put many more miles on them on a bike with a better cable line and a 160mm rear rotor before making any real judgement. First impressions are good -they did feel more powerful than the Spyre- and it’s nifty that TRP was able to pack all that into such a small form factor. One important note if you’re considering them is to look at your bike’s cable runs. The HyRD’s cable entry is lower and more forward than standard cable-driven calipers, and if your bike would require an abrupt bend to get the hose and cable into the caliper, you should double check placement and overall fit before bolting them up and heading down the hills.
For TRP’s launch, they pre-bed the rotors and pads and had the brakes ready to ride. On my Spyre test ride, I intentionally started out by getting up to speed (30+ mph) on a descent, then performed three “emergency stops” down to a crawl, each time sprinting back to full speed before repeating the process. These initial stops were pretty good. They didn’t have the bite of hydraulics, but they did the job. From there, the descents and turns were such that I had to feather or drag the brakes a fair amount in order to maintain sane velocities. After a bit of that, I needed to slow aggressively for a sharp turn, but there was a noticeable fade and I overshot the corner slightly. As did the guy behind me, but other riders had solid performance throughout the entire descent.
TRP’s folks made a bigger deal about the heat management on the HyRD but no real tech talk on the Spyres. So it could have been pad glazing, or something else: There seemed to be a few of the bikes that suffered from pad and/or rotor contamination (grease or oil prevented maximum friction). It wasn’t from anything leaking, but likely due to less than ideal conditions during the installation the night and morning before we all showed up. So, my first inclination is that the Spyre is more ideal for the gravel road and cyclocross market than the performance road rider, but longer term testing with a clean install could upgrade that assumption.
Overall, the feel is good, better than single-sided mechanical brakes and with better rotor clearance. That they don’t bend the rotor every time you use them is a bonus. What’s most impressive is they were able to solve the key issue with standard mechanical disc brakes and come in considerably lighter than what else is out there. And they’re comparatively cheap.
If you’re waiting to get your hands on a set of HYRDs or Spyres, they should be in stock the first week of May