Tuesday, 7 January 2014

Reducing the Rockshox Pike RCT3 Solo Air travel

<Update: I have opened up the comments. Please see the comments section at the bottom of the page for an update on the issues that have been raised>

As part of my new Santa Cruz Solo build, I recently changed the travel of my Rockshox 27.5 Pike RTC3 from the original 160mm to 140mm. I have been asked by a number of Mtbr members if I could document the process for the benefit of the general community.

Here is a table outlining the travel options to help determine the necessary air shaft length and recommended number of bottomless tokens for your wheel size. This is the same table from the Pike manual, I have just added the air shaft part numbers (the ones that have currently been announced). Some shaft lengths are compatible with multiple wheel sizes.

The air shafts have the specified travel marked on the bottom of the air shaft:

I have pretty much taken the instructions straight from the Pike manual (http://cdn.sram.com/cdn/farfuture/siWyhQzGiJhPG8iWT49C8QFszDSWdLtzC8TSQnymhtM/mtime:1385417915/sites/default/files/techdocs/gen_0000000004461_rev_a_2014_pike_service_manual_0.pdf) However, I changed the order specifically to suit the task of reducing the travel. I have also included a few notes and tips, and I have added my photos of the procedure.
I will start off the procedure with an exploded view of the Pike RCT3 Solo Air which provides a better idea of what the air shaft assembly looks like (note the order of the Solo air piston, top out bumper, backup ring, wave spring, Solo Air seal head and rotating ring)...

Rockshox Parts needed:
  • RockShox 0w-30 suspension oil
  • Suspension specific grease (SRAM PM600 Military Grease, Rockshox Judy Butter, Buzzy’s Slick Honey)
  • RockShox Pike Air Shaft (Solo Air) - See travel options below
  • New crush washer (supplied in Pike Solo Air Full Service Kit or Basic Service Kit - I used a spare from my Revelation service kit)

Tools needed:
  • Bike stand
  • Rubber mallet
  • Large screwdriver
  • Small screwdriver
  • Pick
  • Large internal snap ring pliers
  • Schrader valve core tool
  • Long plastic or wooden dowel
  • Clean, lint-free rags
  • Isopropyl alcohol
  • Shock pump
  • Torque wrench
  • Loctite Threadlocker Blue 242
  • 2.5mm hex wrench
  • 5mm hex wrench

Lower Leg Removal

  1. Remove the air valve cap from the top cap located on the non-drive side fork leg.
  2. Use a small hex wrench to depress the Schrader valve and release all of the air pressure from the air chamber. Use a Schrader valve core tool to remove the valve core from the valve body. Cycle the air shaft a few times to release the remaining trapped air.
  3. Use a 2.5mm hex wrench to loosen the set screw and remove the rebound adjuster knob located at the bottom of the drive side fork leg.

  4. Use a 5mm hex wrench to loosen both bottom bolts 3 to 4 turns
  5. Place an oil pan or bucket beneath the fork to catch the draining fluid
  6. Use a plastic mallet to firmly strike each bottom bolt to dislodge the air and damper shafts from the lower legs
  7. Use a 5mm hex wrench to remove the bottom bolt from the lower legs firmly pull the lower legs downward until fluid begins to drain. Continue pulling downward to remove the lower legs from the fork

    There is a noticeable difference in the sensation/sound when you tap the bolts with the mallet, you can actually feel the shafts dislodging. I found that I was able to slide the lowers down once I got the lowers past the 10% sag indicator. If the lower legs do not slide off of the upper tubes or if fluid doesn't drain from either side, the press fit of the shaft(s) to the lower legs may still be engaged. Reinstall the bottom bolts 2 to 3 turns and repeat step 6.
  8. Leave the lowers in the bucket to continue to drain.

Solo air travel change adjustment
  1. Verify all air pressure was removed earlier during lower leg removal.
  2. Use a 24mm socket wrench to remove the top cap.

    I rounded my top cap slightly by using a standard 24mm socket, which has 1-2mm of a rounded edge before the actual traction so it doesn’t have the required traction for the thin top cap. There have been various recommendations to deal with this, the best suggestions being to either facing/machining a 24mm socket so it sits more flush, or to use a flat wrench (perhaps one specifically designed for this purpose e.g. Lunar bike tools - http://www.lunarbikes.com/tools.htm).
    Side note illustrating the Lunar bike tools:

    The Rockshox set comes with a 24mm wrench (for the air spring) a 30mm wrench (for the charger damper). The pictures below shows the tool profile, how it compares to a 24mm socket, and how well it fits on the Pike air spring top cap. Considering the fit of the Lunar 24mm wrench, I think I may still be okay using my lightly rounded top cap.

  3. Spray isopropyl alcohol on the upper tubes and clean the threads with a rag.
  4. Attach bottom-out tokens as required. These thread on to the bottom of the top cap.
  5. Place your finger over the end of the air spring shaft to prevent scratching the air shaft when removing the retaining ring.

    The retaining ring can pop off fairly quickly and could easily scratch the air shaft in the process. Scratches on the air shaft will allow air to bypass the seal head into the lower legs, resulting in reduced spring performance.
  6. Use a small flat head screwdriver to push the Solo Air seal head tab under the retaining ring.Place the tips of large internal snap ring pliers into the eyelets of the retaining ring. Press firmly on the pliers to push the Solo Air seal head into the upper tube enough to compress and remove the retaining ring.

    This step is very tricky and it took some time to get the technique right with lifting the edge of the retaining ring with the screwdriver while using the snap ring pliers to release the retaining ring. This requires some careful handling and patience. (Apologies for not having any good pictures illustrating this).
  7. Slide the retaining ring onto your finger and release the air spring shaft.
  8. Install the bottom bolt in the air shaft to pull the air shaft out of the upper tube.
  9. Firmly pull on the air shaft to remove the air shaft assembly from the upper tube.
  10. Clean and inspect the assembly for damage. Also note the order/position of the bumper cone, backup ring, new wave spring, and the Solo Air seal head.
  11. Spray isopropyl alcohol on the inside and outside of the upper tube. Wipe the outside of the upper tube with a clean rag.
  12. Wrap a rag around a long dowel and insert it into the upper tube to clean inside the upper tube.
  13. Remove the seal head, wave spring, backup ring and bumper cone from the air shaft, noting the order/position in which they are fitted on the old air shaft, as they will need to be installed in the same way on the new air shaft.
  14. On the seal head of the new replacement air shaft, use a pick or your fingers to remove the outer seal head o-ring and the air piston quad ring. I didn't bother with removing the inner o-ring and scraper because the inner o-rings are really tricky to remove without piercing them.
  15. Apply grease to the o-rings and scraper.

    For some reason greasing the o-rings isn’t mentioned in the Pike manual but this is something that I have always done on my Revelations and it says to do it in the Revelation 2014 manual.
  16. Reinstall the o-rings on the seal head and the air piston.
  17. Install the bumper cone on the new air shaft with the broad base facing away from the Solo Air piston. Install the backup ring, new wave spring, and the Solo Air seal head (in that order) onto the air shaft. Tip: If you are not sure on the order or positioning, refer to the exploded view of the Solo Air Pike at the beginning of the Pike manual.
  18. Apply a liberal amount of grease to the air piston and seal head. Note: The manual says to use suspension specific grease which I presume they mean SRAM PM600 Military Grease. I used Phil Wood grease for this step.
  19. Firmly push the air shaft assembly into the bottom of the upper tube while gently rocking the air shaft side to side. Leave the seal head exposed.
  20. While the seal head is exposed, push the air shaft into the upper tube to prevent scratching when installing the retaining ring.
  21. Then push the seal head into the upper tube.
  22. Place the tips of large internal snap ring pliers into the eyelets of the retaining ring and install the retaining ring into the groove. The tab of the seal head should be positioned between the retaining ring eyelets.
  23. Install the bottom bolt in the air shaft to pull the air shaft out of the upper tube. Check that the retaining ring is properly seated in the retaining ring groove by using the snap ring pliers to rotate the retaining ring and seal head back and forth a few times. The retaining ring should click nicely into place on both side of the ring. Then firmly pull down on the air shaft.

    Retaining rings have a sharper-edged side and a rounder-edged side. Installing retaining rings with the sharper-edged side facing the tool will allow for easier installation and removal.
  24. Use a pick or your fingers to remove the top cap o-ring.
  25. Apply grease to the o-ring. Be careful not to apply any grease to the top cap threads.
  26. Insert the top cap into the top of the upper tube. The Pike manual says to use a torque wrench with a 24mm socket to tighten the top cap to 28 N·m (250 in-lb).

    As mentioned above, I rounded my top cap slightly by using a standard 24mm socket. There have been various recommendations to deal with this, the best suggestions being to either facing/machining a 24mm socket so it sits more flush, or to use a flat wrench (perhaps one specifically designed for this purpose e.g. Lunar bike tools - http://www.lunarbikes.com/tools.htm). The specified torque of 28 N·m is quite a lot of torque and using a torque wrench is probably not that necessary. In talking to a couple of bike mechanics, I have been told that with fork top caps you can pretty much just tighten them until they are tightly secure in place. So, meaning almost as tight as you can make it with a flat wrench but not putting all your weight into it (if that makes sense).

Lower leg foam ring oil bath
The lower leg seal service is not really required for this procedure. However, I will include the foam ring oil bath portion of the lower leg service since I have seen a certain amount of feedback saying that the foam rings were dry and that the original oil levels of the fork were low. So it is worth going through the leg seal service for the purpose of doing the foam oil bath (and re-greasing the dust wiper seals).
  1. Remove the wire springs from both dust wiper seals on both sides of the lower leg assembly.
  2. Place the tip of a large flat head screwdriver underneath the lower lip of the dust wiper seal.
  3. Stabilize the lower legs on a bench top or on the floor. Press down on the screwdriver  handle to remove the dust wiper seal. Repeat on the other side

    Be very careful to keep the lower leg assembly stable and also not to apply too much force against the walls of the lowers as this damage the soft magnesium walls of the fork leg.

    Here is good tip that I wish I followed for this procedure - put the screwdriver shaft and head in an old tube (to kind of wrap the screwdriver head). This will prevent the screwdriver head from scratching the inside of the lowers.
  4. Wipe the old grease and oil off of the dust wiper seals.
  5. Inspect the internal wire springs in both dust wiper seals and check that neither of them were damaged in the process of removing the seals. If so then replace the damaged wire spring from the Pike basic maintenance kit.
  6. Use your fingers to remove the foam rings from inside the lower legs.
  7. In a small shallow tray, soak the foam rings in RockShox 0w-30 suspension fluid and let sit for the duration of the procedure.

    The Park Tool Work Tray 106 has a small compartment that is perfect for this.
  8. Spray isopropyl alcohol on the inside and outside of the lower legs. Wipe the outside of the lower legs with a rag.
  9. Wrap a rag around a long dowel and insert it into each lower leg to clean the inside of the lower leg.
Lower leg assembly
  1. Reinstall the foam rings on the top bushings in the lower legs.
  2. If you have not already done so, remove the wire spring from the new dust wiper seal and set aside.
  3. Insert the narrow end of the dust wiper seal into the recessed end of the seal installation tool.
  4. Hold the lower legs steady and use the seal installation tool to push the dust wiper seal evenly into the lower legs until the seal surface is flush with the top of the lower leg surface.

    I noticed that the seals are capable of easily being pushed in too far, so be careful not to push the seals in too far. This is not something I have ever had happen with my Revelation.
  5. Reinstall the wire spring onto the dust wiper seal.
  6. Repeat step 3 through 5 for the other side of the lower legs.
  7. Apply a liberal amount of grease to the inner surfaces of the dust wiper seals.

    The manual says to use suspension specific grease which I presume they mean SRAM PM600 Military Grease. I used Buzzy's Slick Honey for this procedure.
  8. Slide the lower leg assembly onto the upper tube assembly just enough to engage the upper bushing with the upper tubes.Make sure both dust wiper seals slide onto the tubes without folding the outer lip of either seal or bending the wire springs. I found that the best way to do this is to wiggle the upper tubes gently into the wiper seals, one side at a time.
  9. Position the fork at a slight angle with the bottom bolt holes oriented upward. Angle the syringe fitting in each lower leg bolt hole so as not to fill the shaft. Inject 5 mL of RockShox 0w-30 suspension fluid into the drive side leg, and 15 mL of RockShox 0w-30 suspension fluid into the non-drive side leg.

    The Pike manual warns to not exceed the recommended fluid volume per leg as this can damage the fork. Tip: I found that getting the exact volume precisely right is tricky with the particular syringe I was using (the Stans No Tubes sealant syringe). I did a test run with water into a measuring jug to establish how to get the exact measurement. I then checked the amount of water in the measuring jug to confirm the correct volume of water. With my Stans syringe, to get exactly 15ml of suspension oil I had to fill the syringe just below the 15ml mark and then tap the tubing to make sure all the excess oil dripped out, so that there was only oil up to the nib of the syringe. Also, with the Stans syringe it helped to put the rubber plunger tip in the freezer for an hour or so, makes the plunger move easier.
  10. Slide the lower leg assembly along the upper tubes until it stops and the spring and damper shafts are visible through the lower leg bolt holes.
  11. Use a rag to wipe all excess fluid from the outer surface of the lower legs.
  12. Replace the crush washer on the bottom bolt of the air shaft

    Dirty or damaged crush washers can cause leaks.
  13. Thread the bottom bolts into the corresponding shaft of each lower leg.

  14. Use a torque wrench with a 5mm hex bit socket to tighten the bolts to 7.3 N·m (65 in-lb).

  15. Install the rebound adjuster knob onto the rebound damper bottom bolt.
  16. Use a torque wrench with a 2.5 mm hex bit socket to tighten the set screw to 1.1 N·m (10 in-lb).
    Note: Make sure to hold the rebound adjuster knob in place during installation to prevent damage to the bolt hole.
  17. Refer to the air chart on the fork lower leg and pressurize the air spring to the appropriate pressure for your rider weight.

    Note: You may see a drop in the indicated air pressure on the pump gauge while filling the air spring; this is normal. Also, the lower leg assembly will jolt out as the pressure increases. Continue to fill the air spring to the recommended air pressure.
  18. Thread the air valve cap onto the top cap of the non-drive side fork leg until it stops.
  19. Spray isopropyl alcohol on the entire fork and clean it with a rag

The results - axle-crown and travel measurements before and after

Before: the 27.5 Pike RCT3 at 160mm

Before: axle to crown measures 545mm (from the middle of the axle to the top of the crown)

After: the 27.5 Pike RCT3 at 140mm

After: axle to crown measures 535mm (from the middle of the axle to the top of the crown)

Only draw back is that you no longer get the full range of sag markings.


  1. I have opened up the comments so that you can discuss your experience with reducing the Pike travel, and also you can raise any issues you may have encountered during the process. Sharing your experiences and/or difficulties can help others. It also allows everyone to point out any flaws or specific challenges in the procedure, and thus helping to refine the process. If you want to message me directly you can do so by sending me a personal message on mtbr.com (userid: regularbob).

    Here are the issues that have been raised so far:

    1) Don't use Loctite on the bottom bolts - I had originally included a step on my blog posting which said to use Loctite 242 blue on the bottom bolts but I have since removed it from the posting because using Loctite can make it incredibly difficult to remove the bottom bolts. I had a look again at the manuals, and there's no mention of thread lock in either the Pike or Revelation manuals. I have been doing it on my old RS '09 Revelation 426's so I went back to my notes to try figure out where I got the idea that it was required, and I found it in a Bikeradar Workshop tutorial page that I referenced way back when I did the first lower leg service on my Revelations (http://www.bikeradar.com/gear/article/workshop-rockshox-revelation-lower-leg-service-24649). I suspect that after a season of riding, the thread lock's grip eases to the point where the bolts are removable so it might not be a problem for everybody. But having given this a little more thought, I realise that this is fine and all if you fork only needs attention at service intervals. If you have any issues with seals, etc. and you need to reopen the fork then having the thread lock is definitely not good. Apologies to anyone who may have struggled with removing bottom bolts after following this poor advice.

    2) The before and after pictures showing the travel change were not correct - First off, it's very likely that I didn't have the Pike set up with the correct PSI before I made the travel change. In fact, I distinctly remember that there wasn't that much pressure in the fork when I bought it (so yeah, oversight on my side). So the A-C of 542mm that I started with at the beginning might not have been completely correct. Secondly, I have replaced the after pictures with the correct measurements: travel 140mm = A-C of 535mm. The reason for the incorrect measurement in the after picture was due to a common issue with the pressure not equalizing in the air chamber (see issue 3 listed below).

    3) There is a common issue with the pressure not equalizing in the air chamber - Apparently what happens is the forks sucks in a little or just doesn't extend all the way. The solution is to empty the air chamber, cycle the fork a couple of times, then pump it back up (see the Pike 2014 thread for more info - http://forums.mtbr.com/shocks-suspension/pike-2014-a-861503-29.html#post11015622)

  2. Hi,

    I also asked it on MTBR where I saw you posting too:

    I would like to buy the new 29" 2014 pike. Theres an option Im taking another frame with more travel next year. Which fork is the best for keeping all options open?

    Can somebody please let me know whats possible? With a new airshaft I can:

    - Make the 29" 150 a 140? 11.4018.026.001 (10mm less travel)
    - Make the 29" 150 a 160? 11.4018.026.002 (10mm more travel)
    - Make the 29" 140 a 160? 11.4018.026.002 (20mm more travel)
    - Make the 29" 140 a 150? 11.4018.026.004 (10mm more travel)


  3. Thanks for the very detailed post. Wish they had a 140 option for the 26" wheel size. When they do, I'll be using this as my guide!

  4. Very useful. I echo Ecod. Hopefully someday they will release that 140 air shaft for the 26" fork.

  5. Unfortunately the 140mm air shaft for the 26er Pike hasn't been announced, so still not available yet. However, SRAM has recently announced a 140mm dirt jump Pike for 26ers. So I would expect that the 140mm air shaft for the 26er Pike should soon follow...


  6. Great instructions for rebuild! I am looking only to swap the air shaft for the purpose of reducing the travel. I assume this is only a matter of removing the sliders, swapping the shaft and re- assembly w/ new oil? Can you perhaps provide the simplified steps required?

    1. Actually I detailed this procedure specifically for reducing the travel for Pike RCT3 Solo forks not for rebuild. So if you're looking to reduce the travel on your Pike then the entire procedure is what I would recommend. You are effectively doing a lower leg service as part of the procedure. However, I don't really see any way of getting around this because as soon as you take the lower leg assembly off, you will lose oil from the wiper seals and the foam rings. But more importantly you will lower the oil levels in the lower leg assembly and you will have no way of accurately determining how much it will need to be topped up. The safest bet is to just drain the oil, clean everything, remove the old air shaft and install the new one and then re-add the oil with the correct measurements before reassembly. I hope that helps.

  7. So to be sure, which Air Shaft dis you get?

    1. I ordered the following air shaft part from Bikeman.com:
      Part #: 11.4018.026.003 - RockShox Pike Air Shaft Solo Air 150mm Travel 26/120mm Travel 29 A1

  8. What's the maximum travel I can convert my Pike 29er 120mm travel fork to using a replacement air shaft, as in the article above?

    1. I believe that the maximum travel length is typically designated by the length of the stanchions/upper assembly (CSU on the Rockshox parts list) and the maximum length that the lower leg assembly can support. However, I just checked the 2014 parts list and it doesn't mention any travel lengths for either the CSU or lower leg assembly for the 29er Pike. The assumption I read from that is that the CSUs and the lower leg assemblies are the same for all lengths of travel and therefore the maximum travel length is set by the length of the air shaft. The 2014 parts list shows the following part to be the maximum travel for the 29er Pike:
      11.4018.026.002 - Air Shaft PIKE Solo Air 160mm travel 29” (can be used to change travel to 160mm on 29”) A1

      FYI here's the link to the 2014 parts list: (Pike parts are on page 47)

  9. Thanks for putting this guide together. The shaft part numbers was a great addition. keep it up.

  10. Very helpful! Just wanted to check the air shaft part number you used. Presuming it's 11.4018.026.003? Cheers.

    1. I ordered the following air shaft part from Bikeman.com:
      Part #: 11.4018.026.003 - RockShox Pike Air Shaft Solo Air 150mm Travel 26/120mm Travel 29 A1

  11. Great post. Seeking a solution to a hitch:
    The damper side foot bolt spins - seems that the threads are tighter than the inherent tension on the shaft. Possibly the result of threadlock, but as the second owner of this fork I can't say just yet.
    I tried a few suggestions found on other websites: Turn all adjustment knobs to highest levels (lockout, LSC, rebound), compressing fork with a strap. For kicks I tried extending the fork as long as possible too. Nothing worked thus far, bolt just spins in both directions. I don't have access to an impact wrench (another suggestion), but the bolt spins so freely that I'm doubtful that an impact wrench will be much help.
    So, aside from cutting off the bolt flange, does anyone have any other non-permament solutions to this? I.e., any way to stabilize the shaft from the top adjustment area?
    Thanks again for the great pictorial.

    1. Apologies, it may have been my fault that the previous owner of your fork used LocTite on the shaft bolts. I previously had it listed as one of the tasks in the procedure. It was something I used to do with my old Revelation fork but people had been reporting back that the Pike bolt threads have much tighter tolerances and don't need LocTite. That been said I used the lower grade blue LocTite on my Pikes shaft bolts during this procedure and I didn't have any issues removing them when I performe a lower leg service at the beginning of this season. Although, all the feedback I got about the LocTite made me concerned that I wouldn't be able to get them loose. So I purposely waited a little longer to perform the lower leg service because the blue LocTite does degrade over time, especially on parts that see a lot of vibration. If waiting it out doesn't make the LocTite loosen up for you then my guess is that the previous owner must have used a higher grade LocTite. In which case I believe heating the bolts is the only way to get the LocTite to degrade. I wouldn't suggest trying solvents as this would likely do more harm than good. Someone on mtbr raised this with me and he said he had to use a soldering iron to heat the bolts, which is risky work and a total PIA but after a lot of effort he managed to get the bolts loose. And it's because of his feedback that I removed the LocTite steps from the procedure. I hope you have better luck than he did.

  12. Great post! To clarify, if I were reducing travel from 160 to 140 on a 27.5, I would need two tokens, correct? 1 per 10mm decrease?

    1. From the table, yeah, it looks like SRAM recommends 1 token per 10mm. However, the tokens fall into the realm of customisation and tuning, meaning this is just the guideline but it really depends on how progressive you want the Pike's compression to be. If you do a lot of big jumps and drops or if you're a heavier rider then you might want the compression to be stiffer as it gets deeper into the travel which will prevent bottoming out. But then again you don't want to make the compression get too stiff too early in the travel as this will likely make the fork less supple in the beginning to mid range of travel.

      From what I have sussed out from playing around with my tokens, the number of tokens you want depends on a) your weight and b) your riding preferences. I started out with one token but I found that I wasn't utilising the full length of travel. Even on drops and jumps the o-ring wasn't moving to the full extent of the stanchions, likely because I'm a light weight at 145lbs and because I don't do any drops or jumps bigger than 4 foot. I initially played around with the PSI but still wasn't satisfied because I found that if i lower the PSI too much from the recommendation, the fork begins to dive on heavy pedaling. So I ended up taking out the token and going with the recommended PSI. Now the fork maintains the pedaling platform and it utilises the full travel. Your scenario may very likely be different from mine so I can only recommend playing around with the tokens and the PSI to find what suits you best.

      By the way you can remove the tokens without removing the lower leg assembly. Just release the air pressure from the shrader valve, then compress the fork and then release the shrader valve again (to ensure that there is absolutely no air in the air spring). Then remove the top cap from the air shaft side (the non drive side), then add or remove tokens by threading them on our off of the top cap. Then reinstall the top cap and tighten to torque spec. Hope that helps.

  13. Thanks for the FANTASTIC post! This information is really good and thanks a ton for sharing it :-) I m looking forward desperately for the next post of yours..
    carbon fiber wheelset

  14. Hi, great post!

    One question though, you say 5ml into the drive side and 15ml into the non-drive side. I've seen this in another manual but the SRAM service manual says 10ml on each side. Where did you get your values from? Just want to make sure I do the right thing!


    1. I got the oil levels from the 2014 oil & air levels chart... https://www.sram.com/sites/default/files/techdocs/gen0000000004392_rev_a_rockshox_oil_air_and_coil_chart_2014_0.pdf

  15. Rockshox's spare parts catalog lists more air shaft parts numbers now. I made a quick chart similar to yours.


    Full catalog can be found here, but I won't like direct because it's 30+mb. https://www.sram.com/service/rockshox/7

  16. Nice work man. SRAM should idolize this write up. Very helpful.


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