[CaseyD17]

Hey guys, I'm hoping to get some help with an issue I've been having with my 2018 Rockshock 160mm Pike RC Solo Air where my stanchions are stuck mid-travel into the lowers. It's less than a year old now and Rockshox told me to open a warranty claim with the seller I got it, but I'd prefer to solve this myself if possible. For some context, this occurred in pretty low temperatures (0 deg F) on a casual ride with my trial pup and I've noticed other cases that happened in lower temps as well.





I've noticed that this has occurred to a few people with their solo air RS forks, but I'm having trouble narrowing down my options to a definite solution. And just to point out, I did a ton of research and tried many options before posting this and I understand that there is air trapped in the negative chamber of the fork. :madman:


The methods that I've found and tried are as follows:


Burping the negative chamber with a zip tie through the fork seals


This method involves taking a zip tie and carefully pushing it through the seals into the lowers to relieve any pressure built up in the negative chamber. Done to both the damper and air spring side, you can hear an audible hiss come out as the zip tie breaches the seal. While this does work, I believe it is intended for smaller build ups of pressure (~5PSI). Note that there are different theories on how this should be done regarding if the fork should be pressurized to normal pressures or with zero PSI in it (burp with the fork extended or not). I have tried both methods to no avail.


Add PSI until the fork is fully extended and slowly release pressure


This method involves slowly adding pressure to the fork via a shock pump until the fork is fully extended and then slowly releasing all pressure to allow positive and negative chambers to equalize. I personally did not pay mind to max PSI values as I assume that these correlate to the max PSI without load, so I added approximately 80 PSI passed the max value of 163 PSI to get the fork fully extended. I followed instruction and using a shock pump, slowly reduced the pressure in the fork until there was none left in the fork. This had zero effect on the issue I was facing, though. Was I supposed to use a zip tie and burp the seals as I reduced the pressure?


A firm pull


As simple as it sounds, this seems to have the best success rate. It involves removing the wheel, reinstalling the axle, and then pulling the lowers as hard as possible until an audible pop can be heard and the fork is fixed. I tried this, but I didn't want to cause potential issues and risk the fork by pulling too hard. I've noted that this method requires significant force to be feasible. I don't mind doing this but wanted to consult here to ensure it's a safe bet.


I would be willing to service the fork as I've raced it for a season and rode a lot otherwise, but I'm a college student and it's hard to find time to get out on the trails let alone service my fork. I will, however, prioritize a service if it's the safest method to fix this and avoid any risk of damaging the fork.


Thanks in advance for any help and advice. I just want to (safely) get back on the trails as the weather warms up! :thumbsup:

 

[keen]

“I would be willing to service the fork as I've raced it for a season and rode a lot otherwise, but I'm a college student and it's hard to find time to get out on the trails let alone service my fork. I will, however, prioritize a service if it's the safest method to fix this and avoid any risk of damaging the fork”

With all this thought and writing you could have been half way into a service. Service your fork and then revisit the issue if it still exists.

 

[Aglo]

Keen is right, just do a service do te air chamber.
Either way, your fork is probably in the need of a lower service, so take the chance and do both.

 

[CaseyD17]

“I would be willing to service the fork as I've raced it for a season and rode a lot otherwise, but I'm a college student and it's hard to find time to get out on the trails let alone service my fork. I will, however, prioritize a service if it's the safest method to fix this and avoid any risk of damaging the fork”

With all this thought and writing you could have been half way into a service. Service your fork and then revisit the issue if it still exists.

Keen is right, just do a service do te air chamber.
Either way, your fork is probably in the need of a lower service, so take the chance and do both.

I understand that a service is the optimal way to go and if it were so accessable, I would have done it. With less than five weeks in the semester and being so far north in the middle of nowhere, getting the proper parts shipped here, finding some free time to do it where my avaiablity to do so has to match up with the bike club's open service hours, I am unsure of how realistic getting this done will be.

I know that sounds dramatic, but out of the five weeks left, the last week will have final exams, the week before spent studying for them, and the three left between will have loads of work and classes throughout. So after doing research I saw that people had a quick fix for this that I thought I'd get opinions on as the amount of time I'd save would be substantial and I'd probably be able to take advantage of the few riding opportunities that I may get.

When I get out of school, I will be doing a full service of the bike without question. I'll have plenty of time to do so and getting parts shipped wont take an additional three to five days to get them in. By the time they get here, I'll have a week left before I need to study for finals and even less time to find an opening to do the work. So yeah, while writing this takes some time, it's because I have time between classes to do so, not to be servicing the bike for the mear four or five days that I'll be able to ride it.

Thank you for the input regardless and if another option doesn't arise, I'll do my best to service the fork when the time comes.

 

[Millennial29erGuy]

It is not possible to burp the negative chamber by sticking things through the seals. You should never stick anything into the fork seals

You need an air spring service. They are notorious for not working well in cold temperatures. I use slick honey instead of sram’s crappy “military grease”. Probably does not need new seals if it is only one year old.

 

[CaseyD17]

For anyone who made read this in the future with similar issues, I spent the time to fix this with a DebonAir upgrade kit by Rockshox as recommended and taking care of a 50-hour service at the same time. While I don't understand how this happened, there was a strong vacuum holding the piston within the stanchions. A substantial amount of force was needed to get the safety clip out of the way of the retaining clip (you'll know what I mean if you're in there) that holds the air spring in.









With the upgrade and service done, everything is running smoothly and the bike has been riding great! Thanks to everyone for the help and if you're interested in my opinion on the upgrade or have any questions, head over to my bike's specific thread!

Build thread: Banshee Rune Dream Build