Foix FIT damper service – As hard as it looks?

Bump stops, clean, little grease and locate in lowers so holds them in place 😉

Good stuff, I really appreciate the input chaps – I won’t forget you Loco when I **** it all up later on. 🙂

Remember tighten everything up till it shears and then back it off a 1/4 turn, that’s just right 😯 😉

The oil migration issue, was mainly with the newer spring assemblies, that had the foam ring fitted below the air seal on the piston, these are replaced with scraper/lip seals.

Loco makes a good point here, and its worth reiterating in case anyone missed it.

There was a batch of Fox forks from 2010-2012 which had a design fault. They added a foam ring to the air spring piston to keep the seal lubed and running smoothly. Here’s a pic of the air spring showing the foam ring (yellow) and rubber seal (black)…

However, over time it had an undesireable side-effect of promoting the transfer of oil from the lower fork leg to above the air spring. This had two results – 1. Eventually leaving your lowers in that leg dry, with no lube for the bushings, and 2. Oil being uncompressable, the performance of the air spring was degraded and travel reduced. However, it happened so gradually that it was hard to notice until one day you suddenly realise you are only getting an inch of travel out of a 4 or 5 inch fork.

Fox never really admitted to the problem (I’m guessing American company + lawyers = liability issue), but did quietly tell their service agents to replace the foam ring with a rubber scraper seal anytime one of these forks came in for a service. They were also happy to send out the scraper seal FOC to any DIY maintenance owners who requested it. However, there’s undoubtedly a large number of forks out there still with the problem if they’ve never been professionally serviced, or the owner never noticed the issue. For example, take a look at this thread here

So, if you’re going to pull one of these forks apart yourself, take careful note of how much oil is above and below the air spring (should only be 5cc of blue float fluid above, and the Fox oil volumes table will tell you how much oil should be in the lowers). Then have a look at the air spring itself, and if its got one of those foam rings on it (not to be confused with the foam rings under the dust wiper seals!) then contact Mojo and get them to send you a rubber scraper seal to replace it with under warranty.

ok, more assistance needed! all done, cleaned, fox fluid added, oil added in what appears to be correct quantities from Fox, most of the assembly seems to have gone smoothly.

Problem – putting the controls back on the top assemble on the damper side, it appears that the rebound, lockout and compression controls have all seized together, i.e. once the controls are all back in place they don’t do that they are supposed to. the fork compresses seemingly fine, but then takes literally 20 seconds to rebound. not ideal!

any ideas on trouble-shooting / remedial steps?

so even with rebound on full fast the forks are very slow to return?, if all dials are moving the lockout knob and ball bearings are misaligned and need to be reset, can be a bit fiddly.

well i had all three knobs off to get that top 26mm nut undone. even with none of the knobs in place the whole assembly moves as one. i went through the fiddly process of alligning the bearing / needle / allen key bolts etc, but the compression clicker doesn’t move separately to the rest of it. 😡

You’ll have to stripp the topend of the damper to clean regrease by the sounds of it.

ok, i’ll have another look when i’m home. sounds like all that lovely oil might be coming back out of the fork then! cheers once again.

one last question (i promise!) – is there any way of trying to get it all freed up from the top, i.e. without doing a full disassembly again?

in fact, thinking about it i’m being stupid – i can just undo the 26mm nut on the topcap, plus the bottom nut, drain out the oil and lift the damper out, right?

The lock out hex, will spin out and is cleanble, but you’ll have to remove the detent bearings and and spring from lower down, have a loock at the fox drawings and instructions here: http://service.foxracingshox.com/consumers/index.htm

gotcha, i think from having had it apart already that should all be fine. the only thing i’m worried about is whether the seizing could be do with something internal, i.e. misaligning or damaging some part of the damper assembly mechanism?

Info on re-assembling the top cap parts at the bottom of this page in case you haven’t seen it yet;

http://service.foxracingshox.com/consumers/Content/Service/QuickTech/32Gen3OBRL_ServiceProc.htm

Let us know how you get on!

thanks – i did follow the guidance on reassembly and to be honest thought it had gone smoothly. everything at least appeared to have gone back in the right place etc. and fitted neatly together. the reason i realised all was not right is that the red compression adjustment (i think) on top is not indexed at all. in fact it doesn’t spin independently of the lockout lever. and there is no damping. well in fact there is – far too much with no adjustment at all!

planning to have that side apart again over the weekend to see if there is anything that appears to need freeing up other than the top cap assembly.

It maybe that the rebound rod has lost, the tangs off the lower end and may spin and not adjust anything, this is quite easily done if the rod seizes as the tangs are pretty small so doen’t take much force to do, if you get more issues we can sort it all for you 😀

It must be worth pointing out that if there is too much oil in the damper side, it will lock out.

Are you sure the amount is right? Was the damper completely empty before the new oil went in?

<edit> re-read above; this doesn’t seem to be the issue.

that did occur to me, scott – i cycled the damper mechanism up and down a load of times, and it did appear to be empty. because of limited time to do the job in the evenings it was up on the stand draining for a good couple of days as well, so would have thought it was empty!

i got the volumes from here: http://service.foxracingshox.com/consumers/Content/Service/oil_volumes.htm (line 8 ) so assume i didn’t make some stupid mistake on that, though it’s quite possible!

the fork compresses fine, just rebounds ridiculously slowly and, as above, no adjustment at top cap assembly.

Right, a weekend update. I have got the damper assembly out of the leg but unforunately the Fox info on damper servicing doesn’t seem to include the actual fork I have. I got the topcap apart from the damper shaft, took that all to bits, cleaned and reassembled. I now know the issue is not to do with this area, but at least am now an expert on how it all works!

The problem is that the rebound adjustment shaft is stuck in place – I don’t think that the bottom of it is broken as info I got elsewhere suggests that that would mean the shaft / dial would spin freely and at the moment it doesn’t turn at all.

So, I need to get the damper assembly apart to work out why the rebound shaft isn’t turning. Any suggestions on what could be the issue or what to look for would be very welcome. I need to get a spanner slim enough to fit the nut, as my homebase adjustable doesn’t quite do it!

Progress, it seems, has been made. However, not there yet!

Update from me too 🙂
I had my mates forks apart, and they are NOT FIT forks. So the bike shop was bullshitting him and trying to get him to spend the thick end of £300 on something he didn’t need or want. It’s the Giant Concept store in Guildford if anyone wants to know.
So, I took them apart, left the rebound cartridge well alone, cleaned them out, refilled with new oil both sides as per the info on this thread, and put them back together. No more than that. Easy peasy. (FYI they had the wiper seal but no foam ring on the air piston, unlike the pic above)
The result is that the knocking noise has gone and they feel buttery smooth again for about £3 worth of oil.
Said mate is very pleased indeed. 🙂

Thanks to everyone on this thread for the info and the links. That’s saved someone a big old wedge of cash! 😀

I did mine today as well under the tutelage of Andy at purple bike shed (I wanted to find out how to do the foam and wiper seal every 30 hour service, but once you have it apart it’s pretty easy to do the oil change and new wiper seals anyway). Will be in touch with mojo for the foam ring on the piston replacement for next time. Dead easy!

ok – problem solved and fork working perfectly. 🙂

had the damper assembly sitting there cleaned up but still not working. had a think about it last night. ended up taking another look, and considering that the rebound shaft was stuck, rather than spinning freely. having seen how the rest of the adjustments worked I concluded I’d give it a go to free it up. Got a spanner on it, rather than the rebound dial and gave it a bit of effort anti-clockwise. As if by magic, it freed and unscrewed, with the indexing clicking away nicely.

I think it must have bound with the lockout nut when i put it all back together and screwed in and got stuck when i first re-assembled it. Now all back together and the whole fork is working beautifully. Happy days!

That can also be caused by not holding the rebound adjuster when you tighten or loosen it’s bolt, had to take one to Mojo (still under warranty, so they recommended I didn’t touch it)to be fixed after the owner hadn’t done anything whatsoever to it, and definitely hadn’t tightened it with a long arm allen key 😉

that could feasibly have been it (not the long arm allen key part) – might well have done that on first reassembly, to be honest, can’t be sure.

still, pleased to have got it working again and now i know a lot more about how it works then i did a week ago!

So the bike shop was bullshitting him and trying to get him to spend the thick end of £300 on something he didn’t need or want. It’s the Giant Concept store in Guildford if anyone wants to know.

Pretty shocking that (oh dear, no pun intended!)
S’why I’d always send my forks to TFTuned if there was something wrong I couldn’t do myself. Or maybe now PPTuned 😉

This is quite common, the rebound barrel adjuster gets jammed at the end of adjustment and you can sometimes free it off turning in opposite direction, however sometimes it’ll just snap the rod tangs, it’s best to fully strip the cart and release the barrel, although you do really need the correct shaft clamps to reduce the chance of damaging the cart as the body is pretty thin tube.
Glad you got the cart. fixed 😀

Cheers sir, and thanks again (to you and others who chipped in) for the pointers. As I said, I’ll bear you in mind next time I need something doing. 🙂