Fox shock dilemma

[Croglet]

Hi, 

I've got this Fox Nude EVOL 165mm X 45mm shock. Some dirt got under the seal and caused mayhem. The shock loses pressure down to about 150 psi over the course of a day or so. I took it to my LBS who in turn sent it to Fox in PE (I think?) where it's been for the last 2 weeks. The result of which has been quite frustrating - no parts expected for another 6 weeks.

Anyone dealt with this before? What are my options at this point, aside from selling a kidney in the classifieds? Surely this must be repairable/replaceable without having to bin it and buy a new shock? 

Edit: The shock is with RBC in PE. They are not Fox agents so my frustration isn't with them.




 
  

Edited June 12, 2025 by Croglet

[DieselnDust]

56 minutes ago, Croglet said:

Hi, 

I've got this Fox Nude EVOL 165mm X 45mm shock. Some dirt got under the seal and caused mayhem. The shock loses pressure down to about 150 psi over the course of a day or so. I took it to my LBS who in turn sent it to Fox in PE (I think?) where it's been for the last 2 weeks. The result of which has been quite frustrating - no parts expected for another 6 weeks, no quote on a repair or replacement part and no feedback on whether or it's even repairable or not. So basically no help whatsoever. 

Anyone dealt with this before? What are my options at this point, aside from selling a kidney in the classifieds? Surely this must be repairable/replaceable without having to bin it and buy a new shock? 




 
  

this is a common problem with the Fox Performance series shoks with black anodising. Just asak RBC t replace it with a Kashima coated shaft. The wear mark at the sag point is due to the shock bending under pressure. The score mark is caused by dirt and that is causing your leakage.

I;ve got this t-shirt. The Kashima shaft solved the problem but Fox approved this under warranty

[AR SLABBERT]

Hi@Croglet, unfortunately, unlike your front fork, a rear shock with a damaged stantion will lose air pressure, especially given that the wear line is within the sag point. Out of curiosity, what does the internal shaft look like? Typically, the more catastrophic wear is to the internal shaft, which is prone to most trunion-mounted shocks; the light at the end of the tunnel is, again, unlike a fork, the stantion is quite a bit cheaper to replace. My recommendation once the repair has taken place is to buy a decent fork spray and keep that seal lubricated, once or twice a week, just wipe the stantion down and lubricate the seal.

Best of luck, send me a PM if you have more technical questions, and I'll gladly help where I can.

[BrendanA]

10 hours ago, Croglet said:

Hi, 

I've got this Fox Nude EVOL 165mm X 45mm shock. Some dirt got under the seal and caused mayhem. The shock loses pressure down to about 150 psi over the course of a day or so. I took it to my LBS who in turn sent it to Fox in PE (I think?) where it's been for the last 2 weeks. The result of which has been quite frustrating - no parts expected for another 6 weeks, no quote on a repair or replacement part and no feedback on whether or it's even repairable or not. So basically no help whatsoever. 

Anyone dealt with this before? What are my options at this point, aside from selling a kidney in the classifieds? Surely this must be repairable/replaceable without having to bin it and buy a new shock? 




 
  

not an expert, so take everything I say with a pinch of salt, so if I'm not mistaken, there are quite a few "stations" if that's the right word) that will work in place of that one, it's a matter of finding the right width and length. If thats not an option then a second hand shock will have to do as they are not to expensive. 

[droo]

That's 100% lack of maintenance, and fixing it is an easy enough job when you can get the part. If there are no spares in stock you'll have to wait until there are.  Either that or you're in for north of R10k for a new shock. Your call.

Going forward, you can save yourself the hassle by getting your suspension serviced at the right intervals, which is every 150 hours or annually - whichever comes first. The position of the shock on a Spark means that the lubricant doesn't sit on the seal like it would if the shock was the right way up, so if you want to make properly sure this doesn't happen again, an air can service every 75 hours is advised.

@DieselnDust Kashima won't save you here, lubricant will.

[Croglet]

11 hours ago, AR SLABBERT said:

My recommendation once the repair has taken place is to buy a decent fork spray and keep that seal lubricated, once or twice a week, just wipe the stantion down and lubricate the seal.

I use Bronx stanchion spray religiously, and it seems to work really well, as long as the seals are in good nick ofcourse.  

1 hour ago, droo said:

That's 100% lack of maintenance, and fixing it is an easy enough job when you can get the part. If there are no spares in stock you'll have to wait until there are.  Either that or you're in for north of R10k for a new shock. Your call.

I hadn't been keeping track of the hours between services but yes, I obviously left it too long. It wasn't a gradual thing when it went south though. I'd say it went from fine to how it looks in the pic within just a few rides. 
You say fixing it is easy enough. Do you know who else does it/might have parts and roughly what I'll be in for? 
 

[droo]

31 minutes ago, Croglet said:

You say fixing it is easy enough. Do you know who else does it/might have parts and roughly what I'll be in for? 

IF Fox don't have stock it's unlikely you'll find one just knocking about, it's a pretty specialised part that needs proper (read expensive) tooling and a decent techie to replace. As to cost, I can't quote on RBC's behalf but I'd imagine around R 3 - 4k including the service if that's the only worn bit.

 

33 minutes ago, Croglet said:

It wasn't a gradual thing when it went south though. I'd say it went from fine to how it looks in the pic within just a few rides. 

Things work until they don't. everything can appear fine until something obvious fails. The scratch is one thing, but that wear ring on the sag point definitely didn't happen overnight.

 

34 minutes ago, Croglet said:

I use Bronx stanchion spray religiously, and it seems to work really well, as long as the seals are in good nick ofcourse.

Products like Brunox aren't a replacement for proper maintenance, they're there to complement it and reduce stiction after washing the bike. Most of what you spray on the exposed bit of the stanchion will be wiped off by the wiper seal long before it gets to the main seals. Forks and shocks are lubricated from the inside, and when that lubricant stops working you end up with what you have here.

To add to your pain - once you've recovered from this, send your fork in. They're far more expensive to repair when things go south, and the service intervals are the same as the shock.

[DieselnDust]

4 hours ago, droo said:

That's 100% lack of maintenance, and fixing it is an easy enough job when you can get the part. If there are no spares in stock you'll have to wait until there are.  Either that or you're in for north of R10k for a new shock. Your call.

Going forward, you can save yourself the hassle by getting your suspension serviced at the right intervals, which is every 150 hours or annually - whichever comes first. The position of the shock on a Spark means that the lubricant doesn't sit on the seal like it would if the shock was the right way up, so if you want to make properly sure this doesn't happen again, an air can service every 75 hours is advised.

@DieselnDust Kashima won't save you here, lubricant will.

For sure I agree, maintenance is the real problem especially with upside down mounted shocks. But I also had an issue with my performance shock and that had nothing to do with maintenance but rather a bad batch of shafts with anodising that was not hard enough. it was replaced under warranty.

As mentioned, availability of the Kashima coated shaft is generally better than for the black anodised Performance Shaft because there are less issues with those and that it is a suitable drop in replacement (not an other brands shock airspring shaft).

In terms of wear the Kashima does last a lot longer, regular maintenance included or not. YMMV.

So for now, if a Kashima coat shaft is available then its a suitable replacement part. I don't know the context of any enquiry for the spare part but generally if you ask for a part for a Performance Shock the supplier doesn't offer a part from an equivalent Kashima shock. Maintenance isn't going to fix this particular shock of the OP

[Croglet]

Update:
This whole experience was extremely unpleasant and dragged on for over 5 months involving various companies and individuals. Some of whom were a bit hamstrung by things beyond their control, others didn't even bother responding to me when it came time to making arrangements for repairs. 

The moral of the story should be about service intervals but it isn't, the moral of this story is to take your shock to Cogent Industries in Pretoria. 
These guys had me up and running in a couple of days and I wouldn't have missed out on months of riding if I'd gone there from the start.   

Cue Bonnie Tyler's Holding Out For a Hero... 🤘