Two sounds reverberated around the world when RockShox announced that it was making a dropper post with a hydraulic remote control: the first was a round of applause in the great hope that someone would finally produce a reliable dropper post; the second sound was a great wailing and gnashing of teeth from riders who imagined yet another salad-oil wrestling match with an inanimate object when the time came to bleed the system. Pinkbike's forums and comments are peppered with both positive and negative experiences bleeding the Reverb seatpost control line, so I thought I give it a go and see for myself.
Turns out that the job is pretty easy, and quick too. After the first run-through, I can get 'er done in about 20 minutes. The instructions are available on SRAM's RockShox website
as well. The only hassle is finding the 2.5-weight shock fluid required to make the remote work smoothly (RockShox sells it). In this Tech Tuesday, we go through the simple bleeding process. If you want to shorten or replace the hose, you'll need to buy Reverb-specific screw-on replacement hose fittings to finish the job. If you simply need to unhook one end of the hose to reroute it through the frame or linkage, then the following steps are all you need. What You'll Need:
• 2.5-weight suspension fluid
• Avid/RockShox bleed kit
• Isopropyl alcohol (Windex or Simple Green)
• 6-millimeter open-end wrench
• Torx bits and driver (T10 and T20)
• lint-free rags
• Bike stand is a great help
• bungee or rope to keep front wheel straight
How To Bleed a RockShox Reverb Seatpost Remote Control System
Tips that will make the job go smoothly:
The first and most expensive mistake that most Reverb owners make is clamping the hose, hose fitting and upper slider part of the Reverb in the bike stand. If you've wrecked a Reverb post like this, you are a member of a sizable club. We'd advise the rest of you to loosen the frame clamp and slide the post up as high as you need to clamp the fat part of the Reverb below the seal-head in the bike stand. Also remember to move the hose from harm's way before you swing the clamp shut. You'll get best results with the bike angled so that the remote lever is higher or at least level with the bleed port on the seatpost. Keep the front wheel in place with a bungee cord or a length of rope between the rim and frame.
Step 1 - Begin with the post at full extension. If you are only going to remove one side of the hose, unscrew the seatpost end because you won't have to mess with the speed control valve at the remote side.
Step 2 - Loosen the remote control clamp with a T20 Torx wrench enough so it will slide around the handlebar.
Step 3 - Level remote control so that the bleed port (at the elbow) is at a high point.
Step 4 - Fill one syringe about half to two-thirds full with fluid. Evacuate air from syringe by pushing the bubbles and fluid into an absorbent cloth. Wear eye protection to prevent fluid spew from ruining your day.
Step 5 - Remove bleed plug from seatpost with a T10 Torx wrench.
Step 6 - Screw in empty syringe into seatpost bleed port.
Step 7 - Remove remote control bleed plug.
Step 8 - Screw in full syringe to remote control bleed port.
Step 9 - The two bleed plugs are different: the pointed one goes in the remote module and the one with the O-ring fits the seatpost bleed port.
Step 10 - RockShox says to bleed the system with the speed control in the slow position. I found it works better to bleed the system turned in full fast.
Step 11 - Be sure to keep the syringes upright so the air pockets stay above the fluid stream. Pull a vacuum on the seatpost side while pushing fluid into the remote control side. Watch for bubbles on the vacuum end. When the bubbles stop - or you get down to the last half an inch of fluid on the pressure side, stop.
Step 12 - Reverse the pressure/vacuum cycle until you don't see bubbles evacuating from the system. This should only take a couple of sessions.
Step 13 - Give the remote syringe a strong push and then unscrew the seatpost syringe and screw in the proper plug. It has an O-ring, so the plug only needs to be tightened to a snug fit. A little fluid will escape.
Step 14 - With the seatpost side buttoned up, move to the remote control. Pull a vacuum while you push the button all the way in and then pressurize the button with the syringe to return it. Then use constant pressure and pump the button a handful of times. No bubbles? Great!
Step 15 - Pull a vacuum with the syringe while you cycle the speed control from fast to slow a few times to get any trapped air from that little space. Now, pressurize the syringe and unscrew the dial to full slow. While you have the pressure on, push the control button a couple of times just for good luck.
Step 16 - Give the remote control syringe a hard pump and then remove it and screw in the proper bleed plug. It is pointed, so it only takes a snug fit to seal. Wipe off the remote control and seatpost with a clean rag and some alcohol and give the post a test. It should react quickly to a push on the button. If you have to push the button all the way in or pump it to get the post to slide, you've got air in the line and it's probably in the button. Redo the vacuum/pressure steps on the button and speed dial and try again. If all is well, reset the angle of the remote, tighten the clamp and then zip-tie your remote hose in place. Bam! Job well done.
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