The TRP G-Spec DH brakes make a bold statement, both figuratively and literally. TRP says “no expense [was] spared creating this brake [so] every rider can now stop with world cup winning performance.” I’ve tested these stoppers paired with a set of TRP two-piece rotors, and here’s what I’ve found.
G-Spec DH brakes feature four pistons, offering significantly more stopping power than a set of two-piston brakes. Sintered metallic pads are included with the G-Spec DH brakes, and TRP offers compatible semi-metallic pads for purchase separately.
The caliper integrates heat fins into the design, and like the reservoir at the other end, the whole thing is wrapped in a polished finish. The banjo fitting at the hose connection is adjustable for kink-free hose routing on pretty much any bike.
At the lever, the G-Spec DH brakes feature tool-free reach adjustment to dial in the lever position for finger length and riding style. The lever is said to have been designed by Aaron Gwin himself, with cutouts and a dimpled pattern for improved grip and feel. Out of the box the lever is I-Spec II compatible so it plays nicely with Shimano XT and XTR shifters. A adapter kit is available from TRP to fit SRAM Matchmaker shifters. The split hinge makes swapping bars or brakes a cinch.
TRP makes it clear these brakes run on mineral oil as opposed to DOT fluid. There are pros and cons to running mineral oil in hydraulic disc brakes, though most buyers probably won’t be able to tell the difference. Unlike DOT fluid, the boiling point for mineral oil itself won’t drop over time as water enters the system, has a longer shelf life, and the fluid is non-corrosive. However, mineral oil can be more expensive than DOT fluid, and any water that does enter the system generally pools at the caliper where it may cause corrosion and will boil at a much lower temperature than the mineral oil. As a point of reference, Shimano and Magura brakes generally use mineral oil while brakes from other brands are mostly DOT fluid compatible. (If you want to geek out even more over the differences between mineral oil and DOT fluid, read this.)
The reservoir features a simple design with a two bold cover for easy bleed access. All together, the front set is said to weigh 316g, and the rear brake should weigh a similar amount.
The TRP-25 two-piece rotors I tested are 180mm in diameter and center-lock compatible. Like other two-piece designs, the aluminum center improves stiffness and heat dissipation. Six unique slots are carved into the rotor to clear water, mud, and debris while drilled holes reduce the overall weight to 160.6g each. They’re certainly not the lightest rotors, but they do feature solid construction.
On the trail
I had my local bike shop install the TRP G-Spec DH brakes and Patrick says cutting the hoses, bleeding the system, and bolting on the levers and calipers was a breeze with zero hiccups. Bedding the pads in took a bit longer than expected, though I’m not sure how to attribute this.
There’s a saying that good brakes help you go fast, and while it may sound counterintuitive at first, I’ve found this to be absolutely true, especially in mountain biking. Dependable, consistent brakes allow the rider to scrub just the right amount of speed going into a turn so they’re able to rocket out the other side.
For this reason, I like a brake that offers excellent modulation. An on/off brake can cause more abrupt drops in speed, which the rider needs to make up for by mashing on the pedals to get back up to speed again. The TRP G-Spec DH brakes seem to offer fairly progressive braking power. It’s a light touch at the front end of the lever stroke, but stopping power ramps up nicely toward the end for those “oh shit” moments. I can get away with a light drag on the G-Spec DH lever heading into most turns, and finding just the right spot requires virtually zero thought or hesitation.
Full squeezes on the G-Spec DH brakes offer tremendous stopping power as expected. With the amount of stopping power on offer, medium-weight riders like myself are really limited by tire selection and the trail surface when it comes to braking distance. I have come to completely trust these brakes for quick stops and hangs on steep trail sections to get a peek at the next feature.
I’ve tested the TRP G-Spec DH brakes through a wide range of trail conditions, slashing through creek crossings and picking up plenty of dirt along the way. The rotor channels seem to do a good job clearing grit from the disc, which should improve pad life. I was actually surprised to see how much pad thickness is left. It’s hard to say if this is down to the sintered material, or if it’s the channels actually doing their work, but I’ll take it either way. The other potential upshot is these brakes are quieter than others I’ve tested recently, with no warbling and very few audible complaints in wet conditions.
The Gwin-designed lever feels great, with just the right bend for single-finger braking. I’m a little obsessed with the dimples, and I find myself running my fingertip across the lever whenever I’m feeling bored just to get a little tactile sensation.
TRP says they spared no expense in designing and building the G-Spec DH brakes, and I believe them. What’s unbelievable is that these World Cup winning brakes are priced at $199 (per brake), significantly cheaper than top-of-the-line brakes from other brands. Offering tuned modulation, a baller look, easy installation and configuration, and an excellent overall feel, the TRP G-Spec DH brakes, paired with their two-piece rotors, is truly a winning combination, even for mere trail riders.