Last week we broke news of Shimano's 2013 Dura-Ace road group, which is purported to have disc brakes. SRAM are rumored to be working on something too. The fact is they're coming – disc brakes will be commonplace on road and cyclo-cross bikes soon.
Taiwanese company TRP have beaten these two giants to the punch with their hydraulic road and 'cross disc system, Parabox, which is available now. It's a stopgap, which combines mechanical levers with hydraulic calipers ,but it offers plenty of power and, more importantly, modulation.
Fitting is a lengthy and fiddly process – our workshop manager George Ramelkamp reckons it would take the average home mechanic a couple of hours, if everything goes smoothly. The supplied instructions are good but the project needs a patient and methodical approach.
One thing to bear in mind if you're thinking of buying a Parabox is that it needs 17mm of steerer tube real estate below the stem. If your frame is on the large size this could cause problems. Check out the video below for a closer look at the Parabox and more on the fitting process:
Ride & handling
The Parabox braking unit – made up of fluid, lines, master and slave cylinders (calipers) – weighs 497g. That's comparable to most top-end mechanical discs, once you take cable and housing weights into account. So, it's no lighter, and at US$459/£349.99 it certainly isn't cheaper. It does, however, work considerably better, based on our first few rides with it.
Mechanical disc systems are plagued mainly by friction and housing compression; even with fancy fully sealed cable systems, the 1,500mm span of steel cable and brake housing tends to give a sluggish and mushy feel. The Parabox avoids this trap: the short runs of cable from the shifters to the steerer tube mounted master box run smoothly, and from there hydraulics take over to provide an excellent, firm lever feel, much like the best road calipers.
Power isn't overwhelming. We've ridden the system with a 160mm front rotor and both 160mm and 140mm rear rotors, and both Shimano Di2 and SRAM Red brake levers. In its most powerful configuration – with SRAM levers and 160mm rotors front and rear – the Parabox matches the best mechanical systems we've used.
The big benefit of the TRP system, however, is its better modulation. The Parabox isn't grabby but it only requires a light touch at the lever to actuate. Power then increases in a linear fashion as you put more of a squeeze on the lever. There's plenty of power to lock up the wheel, but like any good brake system, it doesn't trick you into unwanted skids.
Why no score?
We've declined to add a score to this first ride review because, while we've used the Parabox for training and for racing cyclo-cross, we've only ridden with it in the dry. We need to give it a good road test with longer bouts of braking before we can fairly judge its performance. TRP say it handles heat quite well, and are pitching it as a good option for tandems.