(updated 10.08.20)
O.K. so you own a RockShox Reverb? It’s probably the best selling dropper post and there is absolutely no reason why, with a few tools, that you can’t service it yourself.
Rockshox have produced some very good video guides so there is no point trying to produce another, however if you want to try servicing it yourself please read on before you begin. We may save you some money or at least some frustration.
Preamble
Some of the Reverbs we receive have just been serviced or repaired by the owners only for them to fail again shortly afterwards. We also get plenty that have been started and for whatever reason couldn’t be completed.
There are two main components that are the most frequently damaged and need replacing – the top cap assembly and the main piston/inner air shaft and there are a few points to note here:
- The top cap bushing is not available from Rockshox on it’s own so you must replace the entire top cap assembly if the bushing has become or looks like it’s about to de-laminate. Now there aftermarket polymer bushes out there presented as upgrades, however many engineering polymers are hygroscopic, meaning they take on water. When this happens the material swells and becomes tighter, resulting in a stuck post as the Reverb doesn’t have the grunt needed to overcome the increase in friction. We figured that this is the reason Rockshox never used a poly bush for this application. The older basic reverb kits do not include a top cap assembly but the newer ones do. More on that later.
- If the inner air shaft is scored, dented or even has a faint tideline in the anodising then there is the potential for air ingress into the Reverb fluid. This will in turn cause the sinking issue that affects many dropper posts. The Reverb is kept at the top of the stroke by a bed of oil, not the air pressure (which just extends the post). Once you release the switch you are effectively closing a tap, the oil can no longer flow and the Reverb stays at full extension. This is unless there is a bubble in there, in which case the bubble compresses and the post sinks. Again more on the inner air shaft/piston later.
So with the above in mind here are our top tips for making sure things go smoothly:
1.) Make sure you have the right tools (sounds obvious but bear with us on this).
If you are going to have a go at servicing a Reverb yourself don’t even contemplate starting until you have all of the following in front of you:
- Soft jaws/shaft clamps (very important) – you will not be able to disassemble the Reverb correctly without these. Trying to find some that are cost effective can be difficult, so we have manufactured our own complete clamp set that holds every part of the reverb (A1 – C1) which you can buy here or just an inner shaft clamp which you can buy here for A1-B1 models or if you have the later C1 (2020 onwards) model here. If you try to secure the main piston/inner air shaft with the flats of a vice, even with flat soft jaws you will deform the part and have to spend more than what it costs to buy a pair of shaft clamps. In addition securing the lower post tightly enough for you to torque the top cap assembly can be difficult without a shaft clamp for the lower post. Don’t tempted to use the bike frame at this point, especially if the frame is carbon, damage can easily occur.
- Bench vice (or vise if you prefer) an absolute must. Preferably not a flexy fleabay g clamp style one secured to a folding joiners bench. This isn’t just snobbery – the top cap assembly can be tight and difficult to remove.
- Oil Level Tool – Stealth Reverbs only Rockshox part number 00.4318.012.008.
- Reverb bleed tool – only required for non stealth Reverbs. This tool prevents oil loss when setting the IFP height on your seatpost. Rockshox part number 00.6815.066.020.
- Reverb oil height tool – only required for non stealth Reverbs. This enables you to remove the correct of excess fluid from the post before you install the poppett. Rockshox part number 00.6815.066.010.
- Reverb IFP tool – you need this to set the IFP at the right depth for your post, without it you will not be able to get this right and your post will not function correctly.
- Reverb bleed kit and fluid – note that the small bottle you got with your Reverb may only be enough for bleeding, not a complete service. Rockshox part number 00.4318.007.001.
- Reverb service kit – now once upon a time this was quite straightforward and the basic reverb kit Rockshox part number 11.6815.031.000 would be fine for all of your A1/A2 stealth and non stealth servicing issues. It didn’t have everything (poppett seals are not present for example) and for some models you are using an o ring from the kit instead of the factory fitted scraper in the lower seal head, but of all the seals that are most likely to fail this kit has those included. Now you need kit 11.6818.031.004 (stealth version) or 11.6818.031.005 (non stealth) for the A1/A2 Reverb. The older basic kits can still be found sparingly online though we understand that they are no longer in production. For the B1 Reverb you have the option of 11.6818.031.000 for the 200 hour 1 year kit (though this doesn’t have any of the dynamic o rings in it) or 11.6818.031.002 which is the 2 year or 400 hour kit. Your Reverb is a B1 if it has “Rockshox” in gold at the top of the post as shown here:
- Pick – a sharp “S” shaped one preferably. You can buy them on eBay quite cheaply. Plastic cocktail sticks can sometimes be sharp enough and have the added bonus that they won’t penetrate anodised parts if you are a bit too keen, however they never seem to be robust enough for some of the reverb seals in particular the lower seal head.
- 34mm Spanner.
- 23mm crowfoot spanner.
- Circlip pliers for internal circlips.
- Slick honey grease or similar. We like PM600, it’s thicker than slick honey and seems to cling to parts/last a little longer.
2.) You really need the shaft clamps/soft jaws.
The big one that people try to manage without is the soft jaws but you will need to secure the main piston shaft assembly without marking it. This component is anodised much like the stanchions on your forks and it does pass through an air seal. Any marks or indentations caused by securing the main piston shaft assembly incorrectly is likely to cause an air leak. We’ve seen various forum threads where people have advised using golf club shaft clamps and we have seen plenty of those Reverbs where things didn’t go to plan. Please note that for B1 Reverbs onwards a replacement inner air shaft wasn’t released as a spare, meaning that if you damage it you have effectively written off your seatpost!
3.) Make sure you use a torque wrench with the crowfoot spanner to tighten the seal head.
The inner seal head is quite soft and it’s quite easy to damage it or under torque it.
If you don’t use a torque wrench you will get this wrong, and risk either damaging the part or the sealhead coming loose, causing it to fail during your one and only ride of the week.
4.) Make sure the Top cap assembly is tight, use a medium strength Loctite and re-check it periodically.
If the top cap comes loose there will be excessive play in the post. If ridden like this you will see accelerated wear to the top cap bushing and lower bushing. You also may see damage to the threads on the top cap assembly, to the point that they won’t hold the correct torque and that is where things can begin to get very expensive.
In our experience even if you tighten the top cap up correctly and even use loctite you will need to check tightness periodically.
Damage can also occur to the threads on the lower tube and seal head assembly, again expensive – if these parts won’t hold the correct torque as a result they will need replacing. The result is that the o ring around the seal head will leak once the seal head assembly begins to work it’s way loose. Imagine the leverage exerted by a rider’s weight as the post rocks backwards and forwards – it’s a lot of stress, it doesn’t take long to cause some serious issues if there is play present. Make sure you tighten the top cap assembly correctly and check it is still tight periodically.
5.) Use the correct fluids
We see a lot of Reverbs that have been filled with unknown fluids, some of which have begun to damage seals. Some of the fluids we have seen have even begun to damage our gloves in the time we are working on them! You just don’t know what additives are in anything else and they may not play nice with your Reverb seals.