is an abbreviation of sorts for "de-hydraulic" and that's exactly what BikeYoke's cable-actuated conversion for RockShox Reverb Stealth dropper seatposts does. The German-made DeHy kit arrives with the necessary hardware, a remote lever, a length of high-quality cable and housing, and a mechanical actuator that threads into the spot that is usually occupied by the Reverb's "Poppet Valve" hydraulic plunger. Remote levers are configured for SRAM and Shimano direct-mount brake lever bosses.
All of the bits are beautifully CNC-machined from aluminum or stainless steel, and DeHy kits can be purchased directly from BikeYoke's online stores in Germany
or North America
. Complete DeHy kits run $124 USD for the SRAM version we reviewed, and $140 for the Shimano-compatible kits. The DeHy mechanical segment alone is sold for $69.
Installation should be easy for home mechanics who have basic experience with shifter and derailleur assemblies. I had the my SRAM Matchmaker-mounted DeHy working in about 30 minutes using only the kit's printed instructions - and that included re-threading the internally routed housing through the frame of the bike.
BikeYoke put together an instructional video that illustrates how simple the DeHy is to install and, after going through the process, I can vouch for that.
My reverb Stealth dropper's hydraulic remote was returning slowly and on the verge of needing a bleed when I took it on a cold and sloppy ride, where the post became unresponsive and stopped midway into its stroke. Installing the DeHy cable conversion seemed like a perfect way to make lemonade from lemons.
The task requires no special tools - just three open-end wrenches, a cable cutter, some Allen keys and a T25 Torx driver. I used a small flat-head screwdriver to remove and replace the Reverb's internal snap ring and, because I was not planning on returning to the standard hydraulic remote, I cut the hose at both ends, about an inch away from the remote lever and the Poppet Valve, so I could use the hose to fish the new cable housing through the inside of the frame.
Tip: Leave the Reverb hose inside the frame and thread a length of wire, first through the new cable housing and then through the hose. Twist a small wrench on either end to prevent the wire from
The DeHy module replaces the Reverb's Poppet Valve. Both the DeHy and the Poppet use a plunger to push on an internal valve-shaft to unlock the post. The DeHy's cable action, however, feels smoother and more precise.
slipping and then pull the new housing through the frame using the old hose. As long as you use a squeaky clean wire, this method makes short work of a sometimes frustrating task.
Slide a length of wire through both the new cable housing and the Reverb hose, and then use it to pull the housing through the frame.
Twist a wrench on both ends to trap the housing against the hose, and to give you something to pull with.
My DeHy kit was configured for SRAM Matchmaker direct-mount levers, which caused a small dilemma because my left-side brake lever clamp was dedicated to the RockShox Reverb plunger. Luckily, I had a discarded left-side Matchmaker clamp from the front derailleur era. There are probably a million of them tucked away in parts drawers somewhere. If you need one, you could probably trade for a slice of leftover pizza.
I needed to switch out the Reverb brake lever clamp to a Matchmaker type (right).
The new lever can be mounted to the Matchmaker's inboard or outboard position.
Tip: Getting the housing clipped to the proper length is not super critical, but you don't want it to be too short, because too much tension on the housing can pull on the cable and release the post. Leave enough housing between the remote and the frame to turn the handlebar 90 degrees, then estimate how deep your post will set into the frame to figure out the proper length. An inch too long is much better than one too short. Remember, you won't have to bleed the system if you decide later that you want to trim the housing a bit more.
The barrel stop is set 17 millimeters from the ferrule and the cable is clipped short.
The DeHy lever has an eccentric cam that actuates its plunger mechanism.
Truth be told, I could have bled the Reverb's hydraulic remote in about the same time it took to install the DeHy kit. So, assuming that I already had a bleed kit and the proper fluid, I could have saved $125 (had I actually paid for my DeHy) and had a functioning dropper post once again. After riding with the DeHy cable conversion, however, I was convinced that I had made the correct decision.
The shift-paddle-style lever's action is lighter and it feels far more precise - which made it much easier to stop the post mid-stroke for pedally descents than I was accustomed to using the hydraulic button. The radial adjustment of SRAM's Matchmaker brake-lever clamp provides the option to angle the paddle remote like a shift lever, or to operate it vertically, like many riders prefer. I still have muscle memory from the front derailleur era, so I chose the angled position. I was surprised that I did not need any time to acclimate from the push button to the new lever.
I like my dropper posts to extend quickly, and that is exactly what the DeHy does. Depress the lever and the Reverb returns with a snap. A lighter touch on the lever will slow the post's return, but there is no fine tuning feature to control the rate of extension (like the dial adjustment that RockShox built into its push-button lever). I am sure that playing with the Reverb's air spring pressure would enable users to tune the return speed to a degree, but I set the pressure at 250psi and left it there - happy to hear the top-out sound the moment my thumb called for extension.
RockShox's choice to use a hydraulic actuation system provides a couple of advantages over a cable system. The most salient is that, properly installed, the hose can be kinked, pulled and shoved, and the post will still function properly. The second is that it is a sealed system, so it should be impervious to cold, wet and dirty conditions. In the real-world, however, the Reverb's remote often becomes sluggish when temperatures drop near freezing, which is annoying.
The DeHy's cable-operated alternative is sealed from the elements at the seatpost, but is exposed at the remote lever. If you have issues with your cable operated shift levers in freezing or mucky situations, you can anticipate the same from your DeHy. That's a rare occurrence these days, but it happens. On the plus side, the lever action of the DeHy system is more intuitive (both right and left hands mirror the same movement), and the option to set the lever where it works best is a feature that the Reverb's push-button cannot duplicate.
|I'm a fan. RockShox Reverb seatposts have earned my respect as one of the more reliable members of the dropper generation, and I was happy to live with its push-button remote until I spent time with the DeHy conversion. BikeYoke's cable-driven remote and its paddle-type lever are an expensive purchase, but for Reverb owners who want a more user-friendly remote, the DeHy is a delightful improvement. It's a more ergonomic alternative, easier to service, and one less reason to smell like hydraulic fluid while I'm wrenching on my bikes. - RC|