KS LEV - DIY Cartridge Rebuild
If you’ve got a KS LEV that has started sinking, this should fix it. I started this thread quite a while ago and used feedback to improve on it. The process seems to consistently work based on feedback I’ve received. Just the simple process of recharging the system resolves the issue that results after air and oil mix in the chambers. Even without replacing seals, this seems to resolve the issue for a long time however I recently added the specs for the seals with an exploded view of the post so that you can replace them while you’re in there. If you try this, please let me know how it goes. Also let me know if any steps are confusing or if you run into any other issues. I’ll use your feedback to improve the thread. ***If all of this blows your mind, I’ve also performed this service including seal replacement for $50 plus shipping (with additional fees if any other parts need to be replaced) – PM me if this is a route you’d prefer to take***
DISCLAIMER: I’ve done this procedure A LOT. I started on my own LEV, and have since repaired numerous LEVs and Supernaturals. I initially went back into my own LEV multiple times to gain additional photos for this thread. Mine is still running smoothly and I only occasionally go back in to replace seals. I’ve refined this post to be as clear as possible and the method works great. I've also added some tips from mistakes I've made myself. That being said - ATTEMPT AT YOUR OWN RISK.
***ATTENTION: Manufacturer Warning***
I have been contacted by the manufacturer and they have urged me to add this warning to this thread on their behalf:
"The procedure explained by the user in this thread is EXTREMELY DANGEROUS and could result in severe injury or death to the person performing this. These warnings are also clearly stated on our website and in our manuals. This posting may cause some consumers to disregard our warnings and severely injure themselves attempting this procedure listed."
"We at KS USA do NOT endorse the servicing of the oil system, it is factory sealed, and not to be opened by the user as the internals are under EXTREME PRESSURE!"
"We offer a 2 year warranty on our products, so if a customer is having an issue, they can send the post in to us and we will REPLACE the cartridge at no charge under warranty. If it is outside of the warranty period, the consumer can purchase a new cartridge assembly thru their local dealer."
Mike A from KS USA
I’m starting the procedure after disconnecting the remote cable from the post and removing the post from the bike. If you have trouble with this, consult your owner’s manual. Although there is a great instructional video at kssuspension.com to do the first 8 steps, I’ve included these anyway to demonstrate my technique for Step 5, which is far more difficult than appears in the video. Also pay attention to a warning in Step 7 to prevent damage to your DU Bushing. Alternatively, skip to Step 9 to get right to the cartridge section or to the near end to see the exploded view and links to replacement seals. I've also added a section regarding the Supernatural differences as this procedure works for it as well, with just a few modifications.
Step 1: With your post in the soft jaws of a vice, remove the end cap using a strap wrench to expose the actuator lever. If you have the 2nd Generation Integra, see differences below (towards the end of this thread).
Step 2: Compress the actuator lever to slacken the internal cable. Rotate the end barrel in order to disconnect it from the lever.
Step 3: Gently pull the cable snug and tape it against the outside of the post with electrical tape.
Step 4: Push the post through or carefully pull on the actuator assembly to expose the inner shaft. Then spray clean with alcohol to prepare for the next step.
Step 5: Remove the LEV from the soft jaws, protect the exposed shaft with a portion of rubber inner tube, then place it in the soft jaws and snug it just enough to prevent the shaft from rotating while you loosen the actuator assembly with a wrench. Alternatively, you could use a rubberized soft jaws like this (but I don’t tend to have good luck with it):
**THIS STEP MAY BE VERY DIFFICULT DUE TO A STRONG THREAD LOCK ADHESIVE – THE ACTUATOR LEVER IS A SOFT METAL AND CAN BEND EASILY – TAKE CARE NOT TO DAMAGE IT - ** (((EDIT))): LESS TOOLS ARE BETTER HERE IF POSSIBLE – SOME ACTUATORS MAY NOT BE AS DIFFICULT TO REMOVE AS OTHERS – VICRIDER222 RECOMMENDS THIS TECHNIQUE: “You will get as much if not more grip by putting on a clean, tight fitting household latex glove and grabbing the degreased shaft with your hand…keep your thumb out, place the shaft along the base of your 4 fingers and close them. Squeeze them as tight as you can, then turn the actuator base with your other hand”
Step 6: Remove the actuator assembly, the rubber bottom-out bumper, and the piston/push rod - **NOTE THAT THERE IS A LONG END AND SHORT END OF THE PUSH ROD – THE LONG END NEEDS TO FACE OUT TOWARD THE ACTUATOR**
Step 7: Loosen the top collar with a strap wrench, then remove the cartridge assembly from the outer shaft. Be carefull not to lose the 3 copper guide bushings on the cartridge assembly. **WARNING – On the KS video, the shaft is yanked with some force so that the copper guide bushings knock the silver DU Bushing out. This works most of the time however if the DU Bushing is stuck, you may blow the inner coated ring out of the DU Bushing (See pic below). You can avoid this buy removing the black top collar, then protecting the stachion with a towel and grasping the DU Bushing CAREFULLY with channel locks and twisting it back and forth slightly to help loosen it (Pictured below though stanchion is not covered to make it easier to see). If you do blow out the DU Bushing, it’s OK. They can be purchased at Universal Cycle
WARNING – avoid this at Step 7
The picture above can be avoided by loosening the DU Bushing using channel locks as pictured below (be sure to protect the stanchion first – (not done here for visability). You just need to twist the DU Bushing slightly in order to make sure it’s not seized before giving the firm pull mentioned in Step 7. BE SUPER CAREFUL IF YOU CHOOSE TO DO THIS AS YOU CAN EASILY SCRATCH THE STANCHION – I KEEP SPARE DU BUSHINGS AROUND BECAUSE I PREFER TO REPLACE IF THEY BREAK RATHER THAN RISK SCRATCHING THE POST
Step 8: Remove the 3 copper guide bushings, then slide off the DU bushing, collar, and bottom of the seat clasp
Step 9: Unscrew the Schrader valve cover and release the pressure from the system using a screwdriver/nail/etc.
Step 10: **EYE PROTECTION AND POINT AWAY FROM YOUR FACE - SEE MANUFACTURER WARNING ABOVE BEFORE ATTEMPTING** Using snap ring pliers (or better yet, a spanner tool – Park SPA-2), unscrew the cap of the cartridge, lift the cap slightly, and dump out the oil. There may be a loud “pop” of pressure releasing when you loosen the cap.
Step 11: Flip the cartridge around and use your finger to push the Schrader valve assembly and the other internals through the cartridge as one entity. You may need to use a dowel rod or protected screwdriver to push it all the way through.
Step 11 b: You can now break the internals down further as pictured below – **WHEN REMOVING THE SLIDING PIECE OF BLACK PLASTIC (INTERNAL FLOATING PISTON – IFP) FROM THE METAL TUBE IT’S ON, IT IS VERY DIFFICULT TO GET BACK ON BECAUSE OF A VERY TIGHT SQUARE GASKET ON THE INNER SURFACE – SEE TRICK MENTIONED BELOW TO REINSTALL IFP ONTO TUBE**
**BE CAREFUL REINSTALLING THIS – YOU CAN SEE THE INNER SEAL HERE THAT I DAMAGED TRYING TO GET THIS THING BACK ON THE METAL TUBE** The best technique to get the IFP back on the tube was demonstrated by “chukt” on page 14 of this thread. Simply use a Craftsman 10 mm socket – it has the same outer diameter as the tube. The IFP can easily be slid onto the socket over the rounded edge, then slide the IFP directly off the socket and onto the tube.
Step 12: Next, replace the valve assembly and the metal tube with the IFP on it. You will want the IFP approx. 2-3 mm away from the end opposite to the valve assembly end. You can assemble these and insert them as one entity. The IFP may need to be guided using your finger to keep it from slipping up further as you replace the tube it’s on. You can also reinstall the cartridge end cap after this step to help push it down approximately 3 mm.
Step 13: Add Fork Oil (I use 5 WT) to fill the cartridge at least to the bottom thread (though I go a little farther for good measure).
Step 13 b: Preparation for step 14: When I went back into my own LEV, I noticed that the coated inner rod on the damper assembly was partially unthreaded (you can see a small gap just below the coated shaft on the first picture below – the second picture is after I rethreaded it down tight). This should be checked before step 14 because if it’s unthreaded slightly, the actuator push rod within the shaft will not be able to fully reach and activate the dropper. You will need to unthread this anyway if you plan to replace the seal in there.
Step 14: Insert the push rod (being sure the long end faces out toward the actuator). Then install the push rod cover. This will allow you to open the valve as you insert it into the oil in step 14 b.
Step 14 b: While depressing the actuator piston to open the valve, insert the damper assembly through the oil and down into the inner metal tube of the cartridge assembly just until the gold coated part is leveled with the top end of the inner tube. Oil should be overflowing as you do this, which should prevent air in the chamber. Tighten the cap using the spanner/snap ring pliers. **USE CAUTION WHEN TIGHTENING THIS AS THE CAP TENDS TO WANT TO CROSS THREAD – ALSO, IF YOU START TO GET RESISTANCE WHILE THREADING, IT HELPS TO TIGHTEN A LITTLE, THEN DEPRESS THE PISTON, TIGHTEN A LITTLE MORE, DEPRESS, AND SO ON**
Step 15: Use a shock pump to add pressure to 150-250 psi. After you’ve added some air, depress the actuator piston to be sure the post is fully extended before filling to the desired pressure. After you’ve added air, with the internal shaft fully extended, you can attempt compressing it against your workbench – if it doesn’t sag, you’ve succeeded in eliminating the sag issue.
Step 16 to finish: Simply follow the KS video to finish the reassembly. Here’s the video:
KS LEV Service - YouTube
**One problem you may run into is when threading on the post end cap. As advised by the video, you thread it on until the last few threads, then use the remote to activate and compress the post before tightening the last few threads. If the post won’t stay in the down position, tighten the end cap a little more and try again before you freak out.
Please let me know how this goes if you try it. Additionally, if there are any really confusing areas or you feel there is some editing I need to do, please let me know.
Also, thanks to everyone for the tips on posting, using Photobucket, and improving my technique.
*Additional Useful Information:
If the internal cable is broken, replacement is pretty easy following this video from the KS Website: KS LEV Service - YouTube
Ron Easton used to be pretty good about mailing you replacement parts but it seems things have changed and now they direct you to your local dealer. If you’re impatient like me, I’ve listed ways to have an endless supply of cable and isolator pellets to do this repair. (You can reuse the metal end barrels, but you need to use a lighter to melt the old isolator pellet out of there before passing the new cable through).
1 mm Braided Kevlar Kite String:
Free Shipping 100ft 250lb Braided Kevlar Line for Fishing Camping Kite Flying | eBay
"Isolator Pellets" This is bean bag filler - they're a little big but you can easily snip them down smaller with wire cutters to get the size you need:
Darice Bean Bag Filler Plastic Pellets, 16 oz: Crafts : Walmart.com
If you prefer the actual parts, Art’s Cyclery is a great source
Barrel (missing the grub screw which can also be purchased at this site) *Again, you can reuse your originals – just use a lighter to melt out the old isolator pellet:
Kind Shock Lev Barrel Cable Clamp Each
Kind Shock Lev Kevlar Link Cable
Another great source for a lot of KS parts:
Universal Cycles -- Kind Shock Seatpost Service Parts
I ran into this issue while examining my buddy’s broken LEV. His actuator lever assembly actually busted through the bottom of the post end cap. There is a lip on the actuator assembly that makes contact with a lip inside the end cap and it appears this holds the entire weight of the rider. In the picture here, you’ll see the lip is “stripped” on both the actuator and cap (using an allen key in the photo to point it out). When weight is placed on the saddle, the post begins to sink into the cap, eventually breaking the internal cable, then jamming the lever against the bottom of the cap. Once the lever hits the bottom, the post is locked into the activated mode (sinks when weighted, rises when standing). Be sure you examine yours if you dismantle it.
LEV EXPLODED VIEW AND SEAL SPECS (LABELED BY MODEL NUMBER):
B70016 -016 N70 Buna-N Nitrile 70 O-ring [B70016] : The O-Ring Store LLC, We make getting O-Rings easy!
N2.00X008 2mm X 8mm Metric Buna-N 70 O-ring [N2.00X008] : The O-Ring Store LLC, We make getting O-Rings easy!
B70009 -009 N70 Buna-N Nitrile 70 O-ring [B70009] : The O-Ring Store LLC, We make getting O-Rings easy!
QR-109 109 Buna-N 70 X-Rings / Quad-Rings [QR-109] : The O-Ring Store LLC, We make getting O-Rings easy!
B90007 007 N90 Buna-N Nitrile O-ring Duro 90 [B90007] : The O-Ring Store LLC, We make getting O-Rings easy!
N1.00X002 (X2) 1mm X 2mm Metric Buna-N 70 O-ring [N1.00X002] : The O-Ring Store LLC, We make getting O-Rings easy!
QR-113 113 Buna-N 70 X-Rings / Quad-Rings [QR-113] : The O-Ring Store LLC, We make getting O-Rings easy!
114 Buna-N 70 X-Rings / Quad-Rings [QR-114] : The O-Ring Store LLC, We make getting O-Rings easy!
MUU-10X15X3 MUU-10X15X3 Urethane Metric U-Seal [MUU-10X15X3] : The O-Ring Store LLC, We make getting O-Rings easy!
N2.00X017 2mm X 17mm Metric Buna-N 70 O-ring [N2.00X017] : The O-Ring Store LLC, We make getting O-Rings easy!
_____________LEV INTEGRA DIFFERENCES__________________
If you have the 2nd Generation LEV Integra, the initial steps will be slightly different.
With your post in the soft jaws, use a crescent wrench to unthread the bottom assembly from the black casing as shown below.
Then simply skip to step 4.
This is something I originally posted later on page 1 of this thread. I recently tried to edit it and received a forbidden message for some reason so I'm tacking it on here.
My wife's Supernatural needed a little more work than I anticipated tonight so I took advantage of the opportunity and created an exploded view of the post for comparison to the LEV (note that when you reassemble this post, it's actually better to have the IFP at the opposite end than is pictured below):
Of course once I got the thing apart, I realized that these are factory charged and there initially appeared to be no way to recharge the system. Luckily, there were other threads online with people who experienced the same sinking feeling.
There's actually a very small hole within one of the craters on the cartridge end cap - this is the area where snap ring pliers are used to remove the cap:
This hole connects through to an even smaller pinhole beneath the lower o-ring on the cartridge cap. I've removed the o-ring in the picture below to reveal the pinhole:
Once the cartridge is reassembled and you're ready to add air, you have to get a little creative as some other threads have mentioned. I used a basketball inflater wrapped with electrical tape (there's got to be a better attachment that seals better - let me know if you're familiar with this) and my shock pump. **EDIT - you can actually use the inner plastic tubing from a standard piece of derailleurs cable housing around the inflator tip**
Downside is that you can't really get an accurate read on pressure so I just added a little at a time until I got the desired speed of activation. **EDIT - this is not true. You can get an accurate reading. I use the LEV guidelines of 150-250 psi
The other difference over the LEV is that the air chamber is on the opposite end so oil is added a little differently.
When I reassembled this, I pushed the IFP down into the cartridge by itself first, then replaced the middle tube and pressed it down in (luckily it didn't give me problems like the IFP on my LEV). **EDIT - a better way is to keep the IFP on the inner tube and insert them together, then using a thin dowel or other rod, push the IFP down into place**
I then filled that inner tube with 5 wt. oil nearly to the brim, then installed the final inner shaft into the oil (I had to depress the activator lever against my workbench as I installed the inner shaft - only as far as needed to then replace the cartridge end cap)
Next, screwed the end cap on and added air with the terrible taped-up needle tip. Post is working great now so I got lucky. Wasn't exactly a smooth process and took way longer to figure out than I care to admit but it's done now and I figured this may help someone along the way.
Sorry for the rough layout and poor quality photos.
**EDIT - I've since done this on another Supernatural that continues to run flawlessly**
Last edited by cakelly4; 08-21-2016 at 05:34 PM.
Reason: Updated seal specs and tips
LEV Rotational Play Repair
If you have a SIGNIFICANT amount of rotational play in your post (nose of saddle rotates left and right), this should resolve it or dramatically reduce it.
There appear to be 4 factors that affect rotational stability in the LEV:
1. The copper guide bushings – these reside in the grooves in the cartridge/stanchion and slide along the groove tracks inside the black casing
2. The one way roller bearing – if the post rotates one way slightly in the grooves mentioned above, this bearing prevents it from moving back, thus minimizing rotational play
3. The grooves inside the black outer casing – I suppose these may get worn and potentially widen over time
4. The grooves on the stanchion – these can likely get a little sloppy with wear over time and therefore allow a little play.
The first two of these factors can be fairly easily replaced. By doing so, you will greatly reduce any rotational play you may be experiencing.
The following procedure was performed on my wife’s LEV after the rotational play increased to the point of feeling the saddle move beneath her while pedaling. As always, attempt this at your own risk. Mine went very smoothly however damage to your post is possible and once you start the procedure, there’s no going back until you have finished.
1. You will need to purchase a new one way roller bearing and 3 copper guide bushings. Be sure to order 3 guide bushings. They are available for a reasonable price here:
2. I found it easier to get purchase on the old bearing assembly by first removing the nylon inner portion using a screwdriver. Once you do this, you’re stuck and will need to follow through to the end of the procedure before your post is functional again.
3. Next, place your post upright in a vice with soft jaws and use a downhill tire lever (works great) or large screw driver (risk of marring) to gently work the metal outer ring loose. I did a little at a time and worked my way around slowly until it lifted approximately 2-3 mm.
4. Next, reposition your downhill tire lever underneath the entire metal ring. The tire lever was perfect for this and really helps prevent damage to the post – keep that in mind. Gently lever the ring out by working your way around it gradually.
5. Clean the bearing surface and grease it lightly with slick honey or other grease to facilitate pressing the new bearing.
6. Prepare your new bearing. Pay attention to the orientation of the bearing. The surface that should be facing up (visible after installing) has a slightly more prominent and rounded edge when compared to the underside. The first picture below shows the top – it’s easier to see this when you have the bearing in front of you.
7. Gently position the bearing level in the post so that the grooves (guide bushing paths) are lined with the same grooves in the black casing. I used my stanchion with the copper guide bushings in place to line up the new bearing, and pushed it down gently by hand to get it seated.
8. Once the bearing is in position, you can get it partially seated by using your hands to push the bearing down into place. Be sure to apply even pressure all the way around so that it goes in straight.
9. Once you get it evenly seated by hand, you can use a hub bearing press attachment and a rubber mallet to finish the job. I used a Hope Pro II Evo hub bearing press (I can’t remember the size) to gently tap it into place.
10. Reassemble your post as directed. Don’t forget your new copper guide bushings.
Good luck if you try it and as always, let me know if you have any better suggestions, questions, etc.
Last edited by cakelly4; 06-30-2015 at 10:57 PM.
Reason: Additional Service Procedure
KS LEV - DIY Cartridge Rebuild
Excellent work! I've been doing this to my Reverb ever since RS released the videos, but I figured the KS post worked in a similar way. I've been wanting an offset post for awhile now and Rockshox won't make a reverb with an offset. Just curious, do you think the KS dropzone has the same or similar cartridge as the LEV? I would change to that in a heartbeat if I could rebuild a dropzone like you've done here with the LEV.
Don't know for sure. I think the cartridges are supposed to be fairly similar but I have not worked on one. My wife has the Supernatural (very similar to Dropzone) and she hasn't had any sinking issues yet. Since the actuator mechanism is on the top, I imagine there may be some differences in where the oil (or air if any?) goes.
Good point. I will say though that the internals of the KS look very similar to the RS Reverb. The parts look a little different, and some parts are longer than others due to differences in the actuation point, but in the end, it is still 3 tubes with 1 tube extending up and down.
Originally Posted by cakelly4
I'm curious, did you change any of the o-rings on the inside of this post? If the RS Reverb starts to sag, it is pretty much a guarantee that one of the dynamic o-rings (ones that either move with the extending shaft or have the shaft moving along side the o-ring) has gone bad and needs to be replaced. It is a long procedure and maybe I missed the 'fix' step or didn't realize what was being fixed to prevent sagging.
Lastly, you mentioned other threads/forums that have more discussion on this? Can you direct me where these are?
Good question regarding the seals. So far, the posts that I've fixed have done just great after this rebuild with no replacement of internal seals. Aside from mine, the other two I fixed began to have the problem shortly after purchase and so my theory is that there are some bad cartridges out there that already have a small amount of air in them. Alternatively, there could be a slow leaking seal and maybe my repaired ones will fail again sometime down the road. Another theory that I've read in some of the other threads is that by lifting your bike by the seat (with the post in the partially down position) you are potentially creating negative pressure in the system and sucking air into the oil chamber. This is also why I'm interested in receiving feedback from others who try this. Will be interesting to see if the rebuild effectively fixes the problem long-term, short-term, or not at all for some people.
Originally Posted by Laterilus
Here are the other sites that I previously mentioned:
ks lev dropper post sag ?
So I just decided to edit this post because I found this quote from a thread I started on a local forum:
Mischief Bruise Quoted:
"My LEV developed 1" of sag last year during a cold weekend where the highs reached the mid-20's during the day. I called KS and spoke to Ron Easton about it, and he said that colder temps could cause some of the seals to shrink, letting air and oil mix, which was causing that sag. At the time, he said that KS was in the process of re-sourcing those seals from a different manufacturer, so I might recommend getting a new kit from KS when doing this repair."
That thread is located here: Repair Your KS LEV
Hope this info helps
Subscribed -- and many thanks to Chris for taking the time to post the this, saving us the hassle of having to send away the post to KS.
You're welcome. I hope it helps for others as much as it has for my own LEV.
Great step by step. rebuilding adjustable seatposts definitely is time consuming and lots of steps. Especially when you don't rebuild one every day, it is easy to make mistakes. When i rebuild mine, i just hope i don't have extra parts sitting there and be scratching my head saying "where were those parts supposed to installed?"
I wish more people did DIY/write-ups like this. I know how to do just about everything by now but it would have been nice along the way.
Would be in for one of these on the Fox DOSS for when mine inevitably starts having issues.
edit: you really put 150-250psi in a LEV? My DOSS asks for something like 15-20psi max and at my return speed preference it's in the <10psi range, so low it won't register on my pump! haha
Yup. LEV manual states 150-250. I believe factory setting is at 150psi. I'm guessing the air chamber on the DOSS is much smaller than the LEV's
Originally Posted by Alias530
Edit: I mean the DOSS is probably a larger air chamber, hence lower pressure.
cakelly4, that's an awesome step by step, thanks for the effort you've put into it. I was looking for something like this and nearly gave up. I don't need to service the cartridge just yet, but I know one day I'll need these instructions.
I have an issue maybe you can help with given you've done a few Levs already:
I've just done the basic service on my Lev for the first time based on the KS youtube video, just cleaned everything and re-greased using Slickoleum.
After reassembly the post is super smooth but I hear loud "breathing" when the post compresses and expands. I can hear air getting sucked in and out through the cable junction under the red KS logo cover where the cable terminates. Initially I wasn't concerned by that, just assumed that it might be because I used a bit more grease than necessary.
But after the first ride following this service I discovered that the silver bottom from the bottom end cap blew out and was rattling inside my frame! Most likely because during the ride I compressed the seatpost quickly, and air did not have time to escape through the cable junction box so it blew out the bottom.
The silver bottom is held in place by an o-ring, just like the cable junction cover so there was no permanent damage and I was able to reinstall it. This happened while the red cable junction cover was held in place by an extra thick after market o-ring and this is why I think the silver bottom blew out while the red cover remained in place.
I have now switched back to the original size o-ring on the red cable junction cover and now when I push the seat post down to test it the red cover gets pushed out by the air pressure. If I don't address it I will probably lose it on the trail. Any idea what is going on? Did you experience this with the posts you serviced?
I thought maybe I wasn't purging the air from the post properly during reassembly. But I don't see how that would matter since the post is able to suck air in through the cable junction box when it expands anyways. I'm at a loss as to how I've "introduced" this issue by the basic "clean and lube" service...
Brings me to the second question:
What is the purpose of compressing the post before the end cap is fully tightened as in the KS service youtube vid? Might it be related to my issue? Note that I did execute this step as per instructions.
Been meaning to reply back to your post. Again, outstanding information and work done here. It's stuff like this that keeps me coming back to MTBr even though the vast majority of the posts on these forums are junk. Good to know there is still worthwhile posts out there.
Originally Posted by cakelly4
Ok, enough gushing; I've re-read your procedure many times over now as it is obviously full of details. I'm a like-minded person and would prefer to sweat all the details.
It is so interesting to me that the designs of both the LEV and Reverb are almost identical, but with subtle differences. One of the main things I noticed was the use of quad seals (I believe you referred to them as 'square gaskets', cakelly4). This was a mistake on SRAM's part. All the internal seals are the typical round seals. I have since replaced all the dynamic seals in my Reverb with quad seals. It made a lot more sense to me to get double the sealing contact for any of the seals that have to move.
The IFP for the LEV is pretty much identical to the Reverb. Yes, those seals are a ***** to get back in, but it can be done with some patience. I squeeze them together to make a little 'taco'. Place your pinky finger or a wooden dowel on the other end just below the recessed area where the o-ring will seat. Once I get one end of the taco in, I'll wedge the rest of the o-ring in the IFP so that it won't pop out, then slowly move the dowel around the recessed area while using my fingers from the opposite end. It's not easy, but it works and you can do this without damaging them if you take your time.
Also, speaking of the o-rings durability, I too am very curious about the run time both you and your friends get from your posts since you did not change any of the o-rings. My experience with the Reverb is that one of the dynamic o-rings has blown if the sagging starts. I like your method of checking for proper operation prior to completely rebuilding the post. I came to the same conclusion with the Reverb. I would like to add something though, after checking to see if the posts sags on your work bench, jiggle the skinny shaft around a bit. If air or oil starts to spray out, the o-ring is blown. Sure, that inner shaft won't jiggle during normal operation, but a good o-ring will still hold that seal with a little bit of side to side movement. I'm sure Kind Shock is like the rest of the manufacturers out there and uses Buna-N o-rings so it shouldn't be difficult to measure them and get replacements. I go to theoringstore.com to get o-rings for my Reverb and forks. Super cheap, and they have quad rings. Comparing to the Reverb, my guess is that the o-rings that tend to go bad are the ones on the two silver end caps, and definitely the quad ring on the skinny inner shaft (the one surrounded by the two teflon glide rings). In addition, I'm assuming the silver end cap you removed using a snap-ring pliers also has an o-ring on the inside of it to seal it around the skinny shaft? That one goes bad on the Reverb as well.
Your bleed procedure is brilliant. One of my main problems with the Reverb is the bleed procedure (for the internal portion of the post, not the remote). The more I looked at your bleed procedure, the more I realized that you are bleeding the LEV upside-down from the way that SRAM has instructed to bleed the post. No matter what I do, I always have 1-1.5mm of sag after a fresh bleed. I don't really notice it on the trail, but it is still annoying and I would like to get ALL the air out of the system. Whenever I get around to bleeding my Reverb again, I'm going to do it upside down using the same procedure you have listed here. The Reverb clamp head actually unscrews from the telescoping post part which would allow for an upside down bleed.
Lastly, I've been looking for a replacement for awhile for my Reverb. Not that the post is bad, I like it a lot, but I wanted the option of an offset seatpost. I fit better on those posts, but I didn't want a mechanical dropper like the Specialized blacklite. I was really considering the KS Dropzone, but there weren't any instructions on how to rebuild them.... that's what has kept me with the Reverb. Now that I've seen your procedure, I'm assuming the general design of the Dropzone will be similar and I'll be able to rebuild that one as well. So, I now have a dropzone in the mail on its way! I'll add to your thread here with a Dropzone re-build next winter (or the first time it starts to sag).
I definitely have experienced the "breathing" sound after servicing the post as you mentioned and would agree that it seems to be more notable when I've gotten a little carried away with the slick honey. I do think a thin smattering is more ideal. That being said, I've never seen the bottom blown out by air pressure alone. I DID however see the bottom blown out of a buddy's LEV where the actuator assembly lip stripped through the end cap lip and busted out the bottom (photos of this are in the above step-by-step) - this is the only reason I knew what you were referring to.
As for the junction box cover, part of your problem may be a worn out barbed ferrule at the junction - the lip is actually designed to mate with an indent in the junction box lid to help keep it in place and to keep the cable aligned properly. The other possibility is that your cover is upside down (with the indent up instead of toward the ferrule). You can buy a new ferrule here: Kind Shock Lev Cable Housing Ferrule Each or ask Ron @ KS to send you one. I've spoken with Ron Easton not too long ago and he mentioned that there is potential for an alloy ferrule to be available soon - thus the barb would be more durable.
The final step in the KS video is designed to prevent an excess bolus of air between the body and the cartridge. I think this step is only to keep a fairly neutral pressure as it seems impossible to keep any air from entering/exiting during operation.
My thoughts would be to go in and lighten up the amount of grease, check your ferrule and junction cover placement, and try again. Also, is Slickoleum thin like Slick Honey, or thicker? Thin definitely seems better for this.
Good luck. Let me know if this was helpful and how it goes. I'm always curious how these issues pan out.
Thanks for the positive praise. Psyched that this thread is helping others even a little. I am a little worried about my IFP after finally getting it back on. I did end up doing pretty much what you explained above to finally get it however I managed to shear a little rubber in the attempts before that. I will definitely keep this post updated as I get more miles on my post and as my buddies do the same. One guy unfortunately doesn't get to ride as often so it may be a while to get better feed back. So far he reports the post as being "sac-slapping fast" though, so that's a plus. The other guy has the LEV that had the stripped actuator so we're currently waiting on replacement parts. So far, the only one I can speak for is mine which has been problem free for miles after the first rebuild. I've since rebuilt it 2 or 3 times just to get more photos for this thread however. So I'm sort of resetting the longevity clock on that one (and with a slightly damaged inner seal on the IFP now - whoops). Definitely going to check out the o-ring website you referenced. And I agree that the quad seals just make more sense for the internals - weird that SRAM doesn't do that. I do wish there was a seal kit for the LEV similar to rear shock air sleeve maintenance kits. That would be the simplest way to maintain them longterm.
Good luck with the drop zone. My wife has the Supernatural and although it's a sweet post, my biggest gripes are the cable connection at the saddle and the external activator arm and cable getting gunked up frequently - her post is being serviced by me as soon as I leave this thread as a matter of fact. It just doesn't do well in excessively wet and/or muddy conditions. I'll soon be creating an under the seat mud guard for hers.
Once again Chris, nice work. Looks like that is what I'm going to have to deal with when my Dropzone arrives as the only thing different between the supernatural and dropzone is the clamp.
First of all, I'm confused as to why this small port is needed to add air. What is the matter with the normal schraeder valve for adding air? Isn't that what you did with the LEV? I think I'm missing something here. I know with the Reverb you add air to the normal schraeder valve once you are finished charging it with oil.
If the small port needs to be used, you could try using some sort or wax or rubber plug. It would be similar to a Fox rear shock when you have to charge the N2 chamber under the IFP. They don't have a schraeder core on their rear shocks, they use a rubber plug. That would produce the seal you want, then you stick the needle through that. It should seal back up as you remove the needle..... or at least that is what I will try when I have to do my post.
It doesn't surprise me that your procedure is a little upside down from the LEV since the valve has switched sides between the two posts.
Yes, I agree about the actuation lever on the Supernatural/Dropzone. It isn't ideal where it is located, but in my opinion, hydraulic is the way to go and I needed an offset post. The only way a mechanical post works for me is if I know the trail perfectly. That way I can set up my post where I want it well ahead of time before I actually need it. The hydraulic posts allow you to drop it whenever, where ever, and you don't have to slam it all the way down for it to be out of your way. I hate trying to 'find' the click in spots. Sometimes I only have time to drop my post 2 inches. That is still better than none at all if I'm coming up to a really chunky spot I didn't know was coming and my speed is a little more than what I wanted going into the section.
Thankfully, I don't ride in muddy areas so this probably won't affect me much. However, doesn't KS already make a mud boot for the supernatural? Isn't it this part?
Supernatural Mud Boot ? KS | Get Down and Dirty
Yeah, that mud boot is on hers but they still tend to get a little gunked up. In fact, I'm convinced that the boot also funnels water and grime down into the cable housing. Mostly a problem in very wet/muddy conditions though.
Now for the bad news: There is no Schraeder valve on the Supernatural (and probably the same for the Dropzone). This is likely due, at least partially, to the reversed chambers which leave no room for a Schraeder valve on the air side of the cartridge.
great post, thanks for the detailed pics. I just finished a relube of my lev which is basically this procedure but leaving the oil cartridge sealed. I used silkolene pro-rg2 grease as I have had a bad experience using slickoleum in the past. in warm temps it gets too thin and runs down to the bottom bracket. hopefully this is not too thick or sticky for the lev.
do you know the size or have a supplier for the o-ring that holds the cable attachment cover on? It appears to be 1/32 width 3/4 ID but I cant find anywhere to order this.
also when disassembling the post how do you pop out the upper bushing without damaging it? for me, the rounded ends of the 3 brass rods were not kind the lower edge of this bushing.
I take it back about the o-ring. metric 1x19mm makes more sense. still interested to see if anyone knows for sure
Not sure what o-ring size. I actually need to do this to mine soon and plan to bring it to the hardware store to find a similar match.
Originally Posted by rox
As for the DU bushing, that's tricky. I definitely ended up with some indents as well. Not sure there's a great way to avoid this. Maybe try gently extending the post until you can feel the guide bushings make contact with the DU bushing, then pull with steady pressure until the bushing pops out of the post body - may be slightly better than pulling hard and slamming them into it. I think the most important part of that Bushing is the inner teflon coated portion. I've gotten a few scratches on that just removing it from the cartridge as it runs over the guide bushing grooves - my recommendation there is to only remove the DU bushing if absolutely necessary to protect the inner surface. Also, Ron Easton was nice enough to mail me a new one when I called and asked.
Have you tried Slick Honey for the grease? In the Supernatural service video found on the KS website, they mention Slick Honey as being a similar alternative to the KS Post Paste. I use a thin smattering of that and it keeps the post buttery smooth.
slick honey is just the marketing (and marked up) name for englund slickoleum. I ordered a pack of 50 1x19mm orings. can send you some if needed and if they turn out to be the right size.
you have much better luck with ron than I do. I bent the upper plate of the seat clamp in a crash and have been trying to get a replacement forever.
I believe the cable junction cover o-ring size is ID=20mm by 1mm. I've tried both 20mm and 19mm and the 20mm comes closer to the original when compared side by side.
Originally Posted by rox
The circumference of the o-ring channel on the cover is around 66.5mm. The internal circumference of the 20mm o-ring is 62.8mm. 59.7mm for the 19mm.
I've recently obtained an obscene quantity of the 20mm X 1mm for cheap. Also happy to post a few to anyone who makes a decent contribution to this thread. Till I run out Just PM me your delivery address.
Thanks for the tips Chris. The red cover was the right way up but I did not push the ferrule all the way up to lock it. The ferrule is new, just replaced one I accidentally cut with the cable...
Originally Posted by cakelly4
I'm pretty sure the silver bottom blew out because of air pressure. If it was from the actuator base slipping past the end cap lip I would have felt it. But I just heard a pop, thought "that's a strange drive train sound" and kept riding...
I've repeated the basic service again, this time paying attention to the amount of grease used. To be honest I don't think it made much of a difference to how much grease ended up inside the mast. The stanchion is 25mm in diameter, while the internal diameter of the black mast is around 25.15mm. So even a light cover of grease is bound to fill the gaps almost completely. The "breathing" is still there (through the gaps around the cable ferrule) but it sounds a bit lighter. The red cover would still try to move out a bit so I put a bit of tape around it and went for a ride. The silver bottom stayed in place this time. I think after a couple more rides when the grease "settles" I won't need the tape on the red cover either.
To be honest I'm not surprised there is pressure build up and loud breathing occurring during operation. It's basic physics. But I'm REALLY PUZZLED why it wasn't there before my first service!
As rox said Slickoleum and Slick Honey are the same thing. I have both at home. They look, feel, smell and taste the same.
I'm in Australia, temperatures have been between 30C and 40C and beyond for the past couple of months (86F - 104F) but the grease has not dripped to the bottom of the end cap yet. The local KS distributor/service centre themselves recommended Slickoleum.
When I serviced my post I did not use a strap wrench. You will get as much if not more grip by putting on a clean tight fitting household latex glove and grabbing the degreased shaft with your hand. To avoid frustration do not try to grab it like a ski pole, it's too short to accommodate your thumb. Keep the thumb out, place the shaft along the base of your 4 fingers and close them. Squeeze them as tight as you can then turn the actuator base with your other hand.
Originally Posted by cakelly4
You'll also find that there is no need to use a wrench to turn the actuator. Just use your other hand which you'll find is capable of producing sufficient torque to eventually twist the shaft out of the grip of your fingers. Tightening it beyond this point is pointless. This is one of those threaded couplings where once the two parts meet and bottom out on each other they won't turn any further. This is why they use thread lock. I cleaned out the original white stuff and used the blue wax based Loctite 248. Just make sure the threads are totally free of slick honey when you apply the threadlock. When I went to do the service the second time I used the glove method with a cheap adjustable wrench on the actuator to break the bond.
I also use the glove on the end cap and the top collar. Just watch the torque because it works so well you might overdo it and damage the threads.
Last edited by vicrider222; 03-03-2014 at 05:20 AM.
I agree that you probably just had air pressure pop yours out (although that's still pretty crazy). You would know if your actuator busted through the post - it becomes unrideable. **Speaking of this, KS is finally sending a replacement actuator for my buddy so we can finish fixing his post and Ron mentioned to him that parts like this and others should soon become available through retailers**
As far as the breathing sound, I agree that it seems more notable right after a service compared to when the post is new. I think any amount of grease just makes it more audible when air passes in and out (like having a snotty nose - typically louder when breathing than a non-snotty nose). I can appreciate a similar sound in the KS video so I consider it to be normal.
Thanks for the info on the technique with the latex glove. I definitely noticed some variation on the 3 posts I worked on. One of them required almost no force at all to remove it despite the fact that it had never previously been serviced. Meanwhile, the other 2 were miserable and I tried everything (including an inner tube) before I progressed to the channel locks, vice grips, and brut force - in that case the thick rubber was more to prevent me from marring that inner shaft. I agree that it would be best however to start with minimal tools to avoid damaging that shaft. When I replaced the actuators, I didn't use any thread lock and pretty much just hand tightened them snugly. I'll go back and edit that step with your recommendations.
Ok, so I got my Dropzone in the mail last night. This is my first piece of KS equipment. I'm definitely pleased with the construction, especially considering the price is much lower than the other top of the line models available from all the manufacturers right now. I'm not a weight weenie, but I like to weigh things just for kicks, so I compared my Reverb (380mm post, 30.9, 125mm drop) to my new KS Dropzone (380mm post, 30.9 clamp, 125mm drop).
<img src="http://c4.staticflickr.com/4/3767/12950939335_f480a896cb_c.jpg" width="480" height="640" alt="RS Reverb"></a>
<img src="https://c2.staticflickr.com/8/7384/12951362874_809f677a43_z.jpg" width="640" height="480" alt="KS Dropzone"></a>
I was actually surprised the KS was considerably more weight. Still not nearly in the range that would bother me, though. If it were over a half-pound difference, then I would think KS needs to do some work.
Even though I was prepared by Cakelly4's previous post on his Supernatural, I decided to get the dropzone anyway since I so desperately needed an off-set post. It seems so very odd to me that KS would design the Supernatural series this way. I understand manufacturers not wanting the customer to work on the cartridge (although, it really isn't that much different from a shock or fork and manufacturers seem to be ok with the end users messing with those), but to not offer the option of re-filling the cartridge with air? That is weird. Temperatures change throughout the year. You need the ability to adjust the pressure in the post to allow it to work properly. Right now, my Dropzone drops and extends at a little under half-speed of my Reverb. Granted, it is cold right now so I know the factory charged air has dropped in pressure, but I should have the option to add more air to compensate. Every other manufacturer (as far as I know) has the schraeder valve setup so you can add air.
While Cakelly4's electric tape-wrapped needle is genius (and hilarious), there certainly has to be another way available to the end user. I found this video on Youtube last night. This is a sweet setup for adding air to the Supernatural series and be able to read the pressure. Too bad I don't know multiple languages. Would be sweet if this guy spoke English. I don't know if he mentions in the video or not how he made the air fitting. I have to imagine there is some item that I can buy that already fits, then simply adapt it back to the threads of a shock pump fitting.
KS 2ªparte,Toma de presion. - YouTube
Overall, I'm very pleased with the quality of the KS products. It looks like to me the quality of the Supernatural series is on par with the LEV, except that the LEV took care of all the very obvious design flaws. Most notably, the air system. Also, I can't tell from the pics, but are all the dynamic o-rings on the Supernatural quad rings like the LEV? I didn't want to open mine all the way without a way to charge it back up with air. I know people don't like the moving cable housing, and the stationary setup of the LEV is certainly nice, but not completely necessary for me. I've always had a moving housing with the Reverb. KS also made a much better saddle clamp with the LEV, although seeing the Dropzone single bolt clamp up close, it is much better than I anticipated. The only gripe I have with it is the length of the clamp istelf. It should have a longer rail holding section to spread out the pressure from sitting on the saddle. At the same time, it is a bonus for me because it allows me to gain even more than 20mm of offset. Sure, this puts even more stress on the saddle rails, but I don't care. I'll replace saddles all day as long as I'm in a comfortable riding position. I also use a saddle with titanium rails. They shouldn't bend as easily as the cromoly, and so far that has proven correct as I've always shoved my saddle as far back as possible. Downside is that titanium tends to break instead of bending, but its break point is beyond the cromoly bend point. Time will tell here.
Speaking of saddle clamps, I am curious if KS simply threaded in the saddle clamp into the telescoping tube (I know for a fact that Rockshox threads in the saddle clamp into the Reverb. It sorta makes me think about a possible franken-KS post in the future. I bet the Supernatural and LEV use the same telescoping post. I wonder if it would be possible to unscrew the saddle clamp from a Dropzone and thread it onto a standard LEV? I wonder....
2 major things I noticed that KS got right over SRAM: First, the brass keys are twice as long. They are thinner than what RS uses, but they also have a tighter fit. I bet there is still more surface area on the KS posts which of course will spread out the load and allow the keys to last longer. In addition, the DU bushing is a separate piece from the threaded collar. it is only $9 to replace as opposed to buying a $40 threaded collar every time that bushing goes bad, and I expect that bushing to last maybe a season considering how far back I push my saddle. Curious though, RS does use 2 bushings instead of 1. They have another bushing to receive some of the 'seated position' load that is located right under the brass keys on the telescoping tube.
As for cable operated systems, I MUCH prefer the KS setup to my Specialized Blacklite (my backup post). The button is awesome! I also didn't know that it could take the place of an ODI collar. Extra bonus! Having the cable adjuster on the noodle was also a nice bonus. Great design. Lastly, removing the cable barrel from the post to do post maintenance is 10 times easier than the blacklite. My only gripe here is there are two 1.5mm set screws. 1.5mm? Couldn't KS just used a 2mm or 2.5mm? Thankfully, I have a high quality wrench set that goes that small.
Cakelly4, you were right about the bottom locknut! Wow, I cannot believe how difficult that was to remove! It's a joke that KS would make service videos showing them easily removing it compared to how it is in real life. The thread locker they use here is the kind that says to me, "We DO NOT want you to remove this nut". Had I damaged something, I would have had a real problem with KS considering they encourage the end user to do the basic maintenance. The Reverb is also setup in the same way, but all I've ever needed were my aluminum soft jaws to hold the tube tightly to remove the bottom nut. I needed to use my aluminum soft jaws (tightened down way past what I do for my Reverb) and two separate vise grips around thick rubber, same as you. I honestly thought I was fractions of a mm away from crushing that tube. That still wasn't enough. I sprayed it with some thread-loosening compound and gave it 15 minutes or so. Nope. I tried using my heat gun. Rarely do I have problems after using my heat gun. Nope. Still not enough. I resorted to holding a lighter on the nut for 2 minutes. Yeah, the nut turned black and so did the red bottom collar, but finally I started to hear the threadlocker bubbling. That was my cue to try again. It made the most God-awful, high pitched screaching/creaking noise, followed by a loud pop. I was certain that I definitely broke something, but it was just the threadlock finally letting go. Ridiculous.
Lastly, (sorry for the long post and slight derail on the thread), but this thread should be followed by everyone that uses a dropper post. It gets old seeing how many people complain and bicker about how their post fails or this or that manufacturer's post sucks, etc... If there is one thing I've learned now from this thread is that all the hydraulic posts out there work pretty much the same exact way. The only differences are minor tweaks to bushings, keys, location of o-rings and location of actuation. Too many people get bent out of shape when it is obvious to me that all of these posts just need regular maintenance. People accept that suspension needs regular maintenance, why not these posts? Suspension has some leniency since it is allowed to constantly move.... and the o-rings still go bad in suspension on a year, to 2 year basis. hydraulic dropper posts are required to hydraulically lock the post in place. That is an extreme amount of stress on those o-rings. They are eventually going to fail... so why not replace them like you would on a fork? It is simple enough to do and o-rings are super cheap, even quad rings. Ok, I'll get off my soapbox. Back to the great discussion here. Also, if anyone figures out a good solution to charge air into the Supernatural series, please post it here!
That video was interesting - mostly because I noticed that he had unthreaded the seat clamp assembly from the post. For the life of me, I could not figure out how to do this and eventually gave up for fear of completely destroying the post.
Although he used a shock pump, I'm guessing his technique is still limited on how accurate to get the pressure. The shock pump seals well on the ball inflator that I used as well. The factor that prevents an accurate pressure read is the internal o-ring covering the pinhole. Once you stop pumping, the o-ring covers that hole, preventing a read. You can read the pressure as you inflate but I'm certain this is not very accurate.
If you decide to add air to your Dropzone, I've come up with an idea that I may try on my wife's Supernatural. Find a small bit of electrical wire with housing that has a diameter similar to one of the craters in the end cap. Strip a piece of the housing off and give it a nice square edge to insert into the crater with the air hole, THEN insert the ball inflator needle into the housing. This should create a snug fit and prevent the problem I had with the electrical tape sliding up the needle instead of sealing. I also had to use pliers to put a slight bend in the needle in order to be able to attach the shock pump (can't remember if I mentioned that).
I may try this soon to make her post a little faster. It performed very nicely on her first ride after service.
I too noticed that the saddle clamp was removed from the cartridge. The one on my Reverb 'naturally' unscrewed itself, but I'm not about to do it to a new post. I then found this:
Originally Posted by cakelly4
Kind Shock Seatpost Service Parts (100108898) at CambriaBike.com
LoL. So at one point, KS was selling the full cartridge kit! That's nuts if the only problem is low pressure! I would have loved to sit in on the design meeting when it was decided the little air hole with the o-ring is the best idea for filling the cartridge with air.
I tried the tape method on the needle last night and failed miserably. I had this whole plan setup where I was going to use a 90 degree bend fitting for a schrader valve, a cut down needle with an o-ring to seal the hole, then smash it together in a vise. Problem is, not much room to work with. I may try my method once I get a 90 deg bend fitting, but in the meantime, I like your idea with the wire coverings. I'll try that tonight. My post needs air for sure. It is a sloooow return, but it works well. Just need to get in some more air.
The pressure reading in the video shouldn't be all that off. As long as everything is sealed, once you pump to a pressure that is higher than what is in the post, the pressure in the pump circuit and post will be the same after every pump stroke even though the o-ring re-seals the hole every time. The gauge would simply read the last pressure it saw from the last pump you just put in. The o-ring is just acting like a check-valve after every pumping stroke.
Oh, and the diameter of the hole is 2mm. Maybe I could find some tube that is 2mm in OD with a hole in the middle.
how about a 1mm tube and an o-ring? maybe a pump needle with an o-ring and tape above it to keep the ring from sliding up
<img src="http://farm8.staticflickr.com/7374/12990013234_c2ff77e74e_z.jpg" width="640" height="480" alt="IMG_2682"></a>
<img src="http://farm3.staticflickr.com/2576/12989618165_5b1b9940ff_z.jpg" width="480" height="640" alt="IMG_2815"></a>
<img src="http://farm8.staticflickr.com/7438/12989745573_6aa784150e_z.jpg" width="640" height="480" alt="IMG_2803"></a>
cakelly4, I thought about your idea yesterday about the wire casing then realized I could possibly take it a step further. Why not use something that would make the diameter of the needle slightly larger in an incremental way? Like I mentioned before, the diameter of the hole is roughly 2mm. I measured the needle last night and got 1.8mm. Oh so close. It then occurred to me to try using some small heat shrink tubing around the needle. That increased the needle diameter to 2.5mm. It wasn't too hard to squeeze the needle into the hole and it made a perfect seal! I was able to secure the needle in the air port well enough to the point I didn't need to hold it in. I just pumped up the seat post as if it had a schrader valve. I should have measured afterwards, but I want to say I was able to push it into the air port about 10mm. I slightly bent the needle with my fingers so it wouldn't rub up against the center shaft (as seen in the picture), then I took an extra step and put an old portion of a tire tube around it to make sure I didn't scratch it while pumping it up.
I also proved my theory to be correct. My shock pump read the pressure just fine. Now, it isn't exactly how you would see it on a normal shock or dropper post, but it still works accurately. Again, you have to think of the o-ring that covers the inner hole as a check valve (and a pressure safety valve for that matter). When you first start pumping up the Supernatural, you are only filling the shock pump hose with air. It takes 3 pumps to fill the pump hose to 200psi. The next pump I did I saw the needle raise a little, then drop back a few psi. That was the break point. My dropzone was at 200psi. Pressure simply works over a differential. High pressure always moves to low pressure. The moment I made the pump hose the higher pressure than the seat post chamber, the o-ring (check valve) let loose, and the seat post chamber and shock pump chamber equalized their pressures. At that point, the o-ring closes again since there is no longer a differential pressure. The shock pump now 'stores' the pressure reading on the gauge of the equalized pressure.
I pumped my dropzone up to 250psi. That increased the speed somewhat.... but still not quite as fast as I would like it. Either way, it is better and the post works very smoothly. Now that I know how to get air in it along with your great bleed procedure, I think I'm going to get a lot of good use out of this seat post!
Then maybe one day SRAM will make an offset saddle clamp for the Reverb....
Nicely done. I'll have to check the pressure on my wife's Supernatural after I get some cable housing or shrink wrap. I haven't had much experience with shrink wrap - what size did you get?
crap! I forgot to measure it with my calipers. It has to be 3-5mm, un-shrunk.
My best guess is either 1/8" (3.175mm) or 3/16" (4.763mm).
Amazon.com: Install Bay Heat Shrink 3/16 Inch x 4 Feet: Car Electronics
I just remembered I had some in my house still after having to splice some small electrical wires on another project. It fit perfectly over the needle after I shrunk it with a heat gun, but I'm sure a lighter will work just the same.
OH! and before I forget, it only took one layer of heat shrink. I first thought I'd need to build up a few layers, but not so. One thin sleeve is all it took. You can find heat shrink at home depot in the electrical dept. or at Radioshack. Any store along those lines that will have electrical tools.
cakelly4, I had another question:
What brand of oil did you use for your post bleed? I noticed you mentioned 5wt, but every manufacturer's weights are different. I'm hoping that I have whatever you used so I can test the viscosity. The Reverb uses Maxima 2.5wt oil which is some pretty thin stuff. I'm wondering if KS uses some fairly viscous oil for their posts. If so, I can speed mine up by using a less viscous oil.
I used Buzzy's Shock Nector 5wt.
I use a nearby motorcycle shop anytime I need fork oil. They carry every weight I ever need.
Great thread - subscribed!
Looks like I'll be trying this service soon as my LEV 150 turned into a pogo stick on the last ride.
Perfect!!! I was hoping you would say Maxima 5 wt. Now I know for sure I can get my post to move faster to my liking. I'll use some Rockshox 2.5 wt. (same thing as Maxima 2.5 wt.). It has a much lower viscosity than the 5 wt. and should move through the orifices at a greater velocity.
Originally Posted by cakelly4
I havent used it on the lev yet but I keep motul "light 5w" around for this
Good luck. Let me know how it goes and if you run into any issues with my instructions.
Originally Posted by PerthMTB
I'll be interested to see how well that works for you. Keep us updated.
Originally Posted by Laterilus
Thanks! One thought though, and its something that's stopping me taking mine apart right now, and pondering instead whether I should send it back under warranty.
Originally Posted by cakelly4
Presumably there is some reason all these LEVs are failing in exactly the same way - bad design, premature failure of seals, poorly assembled at the factory, etc...
Because great as your service instructions are, if I understand correctly its basically a bleed of the cartridge because air has got in there? But, I can't see anything that has addressed how the air got in there in the first place, and therefore would stop it happening again.
So, does anyone know what LEV themselves do when they get one returned? Is there a modified part, new design of seals, different oil or something they do to make sure its really fixed?
If we knew this, and it was a part/service kit that was available aftermarket, then this could be incorporated into your service instructions, and I'd be more confident of it being a permanent fix.
I totally agree. If it's under warranty and you don't mind the wait, it's likely worth it to send it in.
From reading several threads, it sounds like they replace the entire cartridge. I've also read a post that stated that KS may be getting seals from a different source since there have been so many problems (a common problem mentioned was seals shrinking when cold, allowing the oil into the air chamber). Whether that has happened, I don't know but it seems there's at least a slight chance that a replacement cartridge may be equipped with these improved seals. Would be a great question to ask Ron Easton.
The main reason for my thread is to provide a quick fix so people can ride the next day, and maybe send it in when they don't have big riding plans for a while. That being said, mine continues to go strong and feels better than it ever has. Maybe no matter how great the seals, oil and air eventually mix and a bleed is the repair.
Hi Chris, yes that makes sense. In fact, apart from being a quick fix for 'pogo stick syndrome', I also think your procedure would be perfect as an annual service even if there isn't a problem.
Anyway, as I'm in Australia and bought my LEV online from Germany I could be looking at a few months turnaround for warranty, so I'd be real interested to know if it's worth it because I'd actually get something new & improved inside, or whether they would basically just do what I could do myself by following your excellent instructions. Maybe if you get an opportunity (or someone else in the US) could ask Ron Easton - I don't think he'd be interested in an enquiry from Australia!
Anyway, thanks for a great thread, and I'll let you know if I decide not to go the warranty route and try out your procedure...
PerthMTB, there is no such thing as a 'permanent' fix. Things wear out, things fail. There are 2 reasons why to follow cakelly4's procedure: First, you unfortunately received a seat post that was improperly put together at the factory. Second, you've either been riding on the post for awhile or simply got a bad seal from the start. Either way, the seals failed and you have to replace them and then do the bleed procedure.
I find people's lofty expectations of these dropper posts very interesting. There is no special magic behind them. They are semi-complex hydraulic systems that are under an extreme amount of stress. What is funny to me is that people expect their suspension to eventually wear out and require maintenance, but when it comes to dropper posts, they are supposed to somehow last forever. Not possible with the current industry design. I say 'industry design' because they are all using the same one. The only difference between these posts and suspension after seal failure is that your suspension can keep being ridden (albeit with horrible performance) and the seat post cannot.
So, what is the solution? Well, they could use better materials of construction over Buna-N for their seals, but if they did that, they would increase the MSRP well beyond a reasonable price range for most people. I know. I'm a chemical engineer and I deal with liquid piping systems all day and seal compatibility with a variety of chemicals. There is better stuff out there, but it comes at a hefty price. The MSRP of these posts is already past $400 and that gets under most people's skin as is.
What if manufacturers hired more competent people to assemble these posts? Then no one would get a dead post at the start. That's another good plan. The problem is, competent people want to be paid a wage that reflects their competency. The more you pay your employees, the more you have to charge for your products. Manufacturers pay good engineers to come up with designs to stay competitive. Those guys/gals do not have time to answer the phones, deal with warranty issues or assemble the products. That's what the lower paid people do. Unfortunately, it has been my experience that all bike manufacturers pick up whatever joe-shmo off the street and then don't bother training these employees on how their products actually work (or anything about their products in general).
So, things seem dire at this point. What is the real solution? Knowledge. Plain and simple. Bike manufacturers annoy me. They make great products, but overall, their product support afterwards is not that great.... and I don't mean warranty issues. Most are pretty good when it comes to warranty, but when the trails are dry and it is beautiful outside, a new part coming my way in the mail is not currently on my bike and without that part, I cannot ride. This is why I don't care much for warranty unless it is absolutely necessary. When it comes to dropper posts, I'm never going to wait on a warranty replacement. Not when there are threads like this online where we can help each other figure it out ourselves. I'd much rather replace 4-5 o-rings that cost me a total of $1, spend one hour of my time fixing it then be back on the trail that day.
Ok, so I got through my first post bleed on the Dropzone last night (Same post as the Supernatural but with an offset saddle clamp). I'd like to say it was completely un-eventful, but there were a few hiccups along the way. Not a huge deal though and it got me thinking more on what I could improve, and in the end, I got the results I wanted.
First things first, I needed to remove the bottom end cap without first evacuating the air. I was a bit nervous as I've seen people open dropper posts, forks and shocks without first bleeding the air pressure. Since there is no way to do that on a Supernatural, I put a towel around it and slowly made turns. Thankfully, a little over halfway through, the air will start to hiss and there is plenty of thread engagement left to where you can allow the air to escape without having stuff fly all over the place.
I poured out the oil in a cup and was amazed at how thick it was. I can see where Cakelly4 got better performance out of 5wt oil. This stuff was definitely more viscous than Maxima 5wt. A quick run through a Ford #5 viscosity funnel confirmed my suspicions. Maxima 2.5wt oil was twice as fast through the funnel as the stock KS oil. I thought about doing things incrementally, but decided to go past the Maxima 5wt and directly to 2.5wt.
I also decided to measure all the o-rings and quad rings while I had things opened up. I do this for all of my forks, shocks and dropper posts because I refuse to pay the elevated prices that bike manufacturers charge for simple o-rings. I went online to theoringstore.com and compared my measured sizes to what they had. These are my best guesses, but I'm pretty sure they are all correct.
Bottom End cap:
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If I don't have something marked, then I couldn't find something comparable online. O-rings that have 2 sizes associated with them could be either of those sizes. These are small measurements and it is difficult to get with perfect accuracy. Sometimes it is a bit of trial and error. One thing I did notice in contrast to the Reverb is how tight each of the o-rings are. I think KS erred on the side of a slightly smaller o-ring to make the seal as strong as possible. On the flip side of things, that causes more friction and slows the post down (which the post didn't need help considering the highly viscous oil they use). In addition, I'm curious if that extra friction would cause faster wear? Time will tell. Also, KS uses a lot of quad rings. This is a great idea, however, I've only ever found quad rings in standard measurements, never metric. I'm sure someone makes them in metric, but I can't ever seem to find them. This makes the sizing a little off in my opinion. Sure enough, KS uses the exact same size tubes (stanchion tube, IFP tube, piston shaft) as SRAM in the Reverb. No joke. All of their inner and outer diameters are the same, and they are all metric. In some places, the quad rings work very well. In others, the size is a bit off and makes it a massive pain to deal with. The quad ring on the piston shaft fits perfectly. The IFP? Wow, massive pain in the ass.
During one of my reassembly attempts, I could not for the life of me get the IFP tube back into the IFP. The inner quad ring was too small to fit around the outer diameter of the IFP tube. I mistakenly though that hitting the IFP tube with a rubber hammer would help pop it in. It didn't. I shredded the inner quad ring on the IFP. I didn't worry though as I knew I had something that could fit in its place as I have many o-rings for my Reverb. Sure enough, a 2.5mm x 14mm metric o-ring fit perfectly. It was still a tight fit, but not ridiculous as the quad ring was. Will it blow out quicker? Don't know until I start putting a lot of miles on this thing. I will say this: SRAM doesn't use quad rings on the IFP and I've never had an IFP o-ring fail. That's in a Reverb, though. The Reverb has the air pumped in through the piston shaft. When the valve closes on a Reverb, all the stress of sitting on the saddle is put into the o-rings on the bottom end cap o-rings and piston shaft o-rings. The Supernatural is a bit different and I think the stress from sitting on the saddle is spread out between piston shaft, bottom end cap and IFP o-rings. If I'm right, it is a slightly better design to spread out the load over more places. Again, time will tell if my standard o-ring holds up. If not, I'll go back to the quad, but I'm not quite sure how I will get the IFP tube through it.
Ok, onto the bleed procedure. KS definitely followed what I've told others in the Reverb thread. You need to push the IFP down at least to the length of how far your post can extend, or past that point. Following Cakelly4's plan will work.
Next, I placed my seatpost in my vise (with aluminum soft jaws) in a way that kept the post stable, but also had the valve depressed at the same time. A little rigging with a cassette lock tool seemed to do the trick beautifully.
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At this point, I do things slightly different from Cakelly4. I was bored and wanted to figure out if there is a way to completely remove all the air from the internal system. I think I was able to do that. Once I had my post in the vise with the valve pressed in, I poured in a small pool of 2.5 wt. Maxima oil (or Rockshox which is re-branded Maxima with some food coloring added in). The pool was maybe 4-6mm deep. I then pushed in the IFP into the stanchion tube by itself all the way to the end (all the way to the saddle clamp). I happened to have SRAM's IFP tool and it works perfectly on the KS posts as well. It's a nice tool because you won't scratch the inside of the stanchion tube while pressing in the IFP (although a piece of PVC pipe the same size would also work fine)
<img src="http://farm8.staticflickr.com/7354/13037011263_2c51edf68a_z.jpg" width="480" height="640" alt="IMG_2834"></a>
My reasoning here is that I do not want to trap ANY bubbles behind the IFP. Any air and oil the IFP contacts as I push it to the end of the stanchion tube will escape up through the inside of the IFP. Once the IFP is in place, then I install the IFP tube. This is where having a very tight quad ring on the inside of the IFP caused me fits. My bleed plan doesn't work if I can't push the IFP tube through the IFP. So I destroyed the quad ring, replaced it, and moved on. The IFP tube displaces a small amount of oil and that just goes slightly up into the IFP tube. Doing this in 2 parts though seals off the IFP perfectly from any air getting trapped underneath it.
I now filled the IFP tube all the way to the top, but I didn't stop. The act of pouring the shock oil tends to make a lot of small bubbles (and a few large ones). I could have just filled the IFP tube to the top, went away for awhile and waited for all the bubbles to float to the top and escape, but I was impatient and stole a trick from the Reverb bleed procedure. If you keep pouring into the IFP tube and let it spill over the sides, it will start to go into the cavity between the IFP tube and stanchion. Don't worry, we don't leave it there. It is just a way to get the air bubbles moving. They'll go out with the oil that spills over the sides.
Once all that air spills out, I pressed in the piston shaft into the IFP tube only until the quad ring on the piston shaft engages the IFP tube. That creates the last seal needed to close the system. I then remove the post from my vise and pour out the excess oil (with air in it) that spilled into the cavity between the IFP tube and stanchion.
I put the post back into the vise and re-setup my system to keep the post steady and have the actuator pressed in. I then took a cue from the other video I posted and used the piston shaft to set the IFP depth. With the valve open, the piston shaft will move the IFP via hydraulic pressure. I simply pushed the piston shaft into the IFP tube until the threads of the bottom cap could engage the stanchion. I screwed the bottom cap back on, pumped my post back up to 200psi, tested it, and sure enough, it didn't drop at all. No sag! Not even 0.5mm. First ever perfect bleed for me on a hydraulic dropper post. The speed of the post was also drastically increased. Still, I wanted a little more so I took it to 250psi. That did it.
Here is a small video of the speed of my post right now. Mind you, the temperature here was in the low 30's when I took this video, so the post is a little slower than what it was last night when I first tested it, but the speed is still plenty fast to be useable on the trail. It should speed up a lot more once it gets hot outside. At that point, I'll probably drop the pressure a bit so it doesn't go as fast as those ridiculous mechanical posts that launch you to the moon while crushing your nuts at the same time.
So that's it. Hopefully this helps you guys out. Remember, the LEV, Reverb, Supernatural, etc. all work the same way (and probably the other hydraulic posts on the market). They can all be fixed by the end user with a little bit of detective work. The only real difference is that you have to think about where is the valve located internally. That will determine where you want your IFP and how you should bleed the system. I thank Cakelly4 for starting this thread to get the creative juices flowing!
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Laterilus, Nice work with the seals identification. Would be nice to have that info for the LEV as well. I damaged the inner IFP seal exactly the same way - death by rubber mallet (in hind sight, a poor choice). In my instructions, there's some tips on how to get it back on from another MTBR member for future reference. Though as you know, it's easier to avoid air in the system if the IFP can be inserted by itself before the shaft it rides on. Hope the seal you replaced it with holds.
PerthMTB, I called Ron Easton and left a message asking about the new cartridges they're providing people with. My thoughts are that if they did upgrade the seals, why not use the warranty to get a new and improved cartridge. I agree that all seals will fail and need replacement at some point, similar to suspension, but if they fail prematurely and have since upgraded the seals, you may as well get a new cartridge out of it. I've read threads where LEVs failed after only 1-2 rides and that's clearly not normal wear and tear. Downside of replacing obviously is the down time and shipping costs. Would be nice to eventually get the specs on the seals or to have a KS replacement kit available for purchase (though likely overpriced as Laterilus mentioned).
The other reason I called Ron is to get information about a possible alloy replacement barbed ferrule. Last I spoke with him, he mentioned that there was rumor of one being available soon and told me to check back in with him at a later time.
I'll keep you posted if/when he calls me back.
Chris, I suspect the standard o-ring I used in place of the quad ring on the IFP will hold considering the IFP o-rings on my Reverb have been fine for 2.5 years. This isn't a complete apples to apples comparison, but it is very, very close. The IFP for both the Reverb and Dropzone are exactly the same. The only difference is that the Reverb uses standard o-rings with teflon glide rings on either side and KS uses quad rings. RS uses 2.0mm thick rings and KS uses 2.5mm to fill the gap where the glide rings would be on the Reverb. Either way, the internal o-rings are the exact same size. The Reverb uses a 2x14mm o-ring and the Dropzone uses a 2.6x13.9mm quad ring (size 113). Considering manufacturing tolerances, essentially the same size o-ring. It's just easier to get the Reverb IFP tube through the IFP since it is only a standard o-ring. The main stress points on the Reverb that eventually fail are the bottom cap and piston shaft. If for some reason the standard o-ring doesn't hold strong in my Dropzone, I'll re-create the Reverb design and change to a 2mm thick o-ring and put teflon glide rings on either side to see if that helps.
Originally Posted by cakelly4
Speaking of the o-ring failures inside the Reverb, I think that ALL of these posts probably fail the exact same way. I'm gonna go out on a limb here and say that in addition to the Reverb and Dropzone (Supernatural), I bet the LEV also uses the exact same diameter for the stanchion tube, IFP tube and piston shaft tube. If that's the case, it also uses essentially the same size o-rings as I've discovered on the Reverb and Dropzone. The Reverb has a few different ways of failing with internal o-rings. First, the o-ring on the piston shaft (with glide rings on either side) will fail, allowing air and oil to mix. Prior to seeing this thread, I had already changed the o-ring on my Reverb's piston shaft with a quad ring just like KS already provides. Same exact size between the two, size 109. Secondly, the large o-ring on the inside of the bottom end cap that seals around the outside of the piston shaft. If that fails, the air leaks out of the post and can't hold you up. Lastly, the o-rings just below the threads of the bottom end cap. I've run into this problem numerous times on a Reverb. The bottom end cap will unscrew itself and eventually, the o-ring can't hold containment and gets blown out and destroyed. The air leaks out and can't hold you up. See the picture below.
<img src="http://farm8.staticflickr.com/7348/13085478305_a3ea909f7f_z.jpg" width="640" height="480" alt="IMG_2867"></a>
Anyway Chris, you could probably get away with getting a lot of the same size o-rings for the LEV and I bet they would work fine. I'll be curious as I go through this season if the Dropzone endcap also unscrews itself over time or if any of the other o-rings go bad. Either way, it is very quick and easy to break it down and get it fixed. Also, since it has the same size stanchion as the Reverb, it can also use the drop-setting collar as a quick fix on the trail to get you out of the woods.
I highly doubt KS has changed their design by making different sized tubes for the LEV. If they have upgraded their seals from Buna-N, I'd love to know what they are using, but I'm guessing nothing has changed. While premature failure sucks pretty bad, it can, and does happen. I certainly understand wanting to get a warranty post replacement, and assuming it works, it will still only work for a period of time. Might as well learn to fix it yourself instead of having down time, but to each their own.
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