Hiya,
So I think I'm in a pickle. SID Ultimate (C1). Started feeling odd.
Trying to service the fork - when I let air out of the main chamber (no matter how slow), the air spring gets sucked all the way in.
There's a lot of negative air which won't equalise... which means removing the circlip will cause a kaboom, right?
My estimate is there's about 50 psi in there.
Personally, I'm not keen on being impaled by a Debon Air shaft.... or any shaft for that matter.
What items can I trouble shoot to get this thing off?
This may be a transfer port issue.
I Google this: rock shox sid transfer port blocked
The AI summary looked mildly helpful but also.
https://singletrackworld.com/forum/bike-forum/pikes-sucking-down-transfer-port-clean/
There was a suggestion in one of the other headline results that dropping the pressure 5 psi, pulling the fork up to fill extension and repeating until empty might work on another thread.
There were various YouTube videos too.
My suspicion is your underlying issue is the transfer port or damage to the air shaft.
Are the lowers off already?
This may be a transfer port issue.
I Google this: rock shox sid transfer port blocked
The AI summary looked mildly helpful but also.
https://singletrackworld.com/forum/bike-forum/pikes-sucking-down-transfer-port-clean/
There was a suggestion in one of the other headline results that dropping the pressure 5 psi, pulling the fork up to fill extension and repeating until empty might work on another thread.
There were various YouTube videos too.
My suspicion is your underlying issue is the transfer port or damage to the air shaft.
Thanks - I re-fitted the lowers, re-inflated until the air spring stopped extending..... then I pulled/stretched the fork.
Upon pulling (or stretching) the fork, I could hear the hiss of it equalising. Dropped 10 psi at a time and repeated until it was sorted. 👌
Gave it a good clean - I was a bit more sparing with the SRAM butter on re-assembly.
Thanks again.
Another way to overcome this is to just pump the positive chamber to 100+ PSI (i.e way more than you would ahve it set at) - this then overcomes the negative side, equalizes the chambers, and THEN you can let the air out again to your required pressure
DrP
Do the Debonair shafts still have the internal valve like the solo air did? if this happened with solo air, you could stick a long thing inside the shaft from the bottom of the fork (with the bolt out) and depressurise the neg side.
The only way I could solve this on my Revs was to sit on the front tyre and curl the bars up until it go past the clogged port with a massive pishhhhhhh. Working good as new now, which is still a bit crap. Moco damper is rubbish.
Another way to overcome this is to just pump the positive chamber to 100+ PSI (i.e way more than you would ahve it set at) - this then overcomes the negative side, equalizes the chambers, and THEN you can let the air out again to your required pressure
Exact same issue as the OP happened to my SID Ultimate fork when I first got it three years ago and the above is what fixed it for me too. Once it had equalised I dropped the lowers and did a lower leg + air spring service with the correct amount of oil and grease and have never has issues since.
Another way to overcome this is to just pump the positive chamber to 100+ PSI (i.e way more than you would ahve it set at) - this then overcomes the negative side, equalizes the chambers, and THEN you can let the air out again to your required pressure
Exact same issue as the OP happened to my SID Ultimate fork when I first got it three years ago and the above is what fixed it for me too. Once it had equalised I dropped the lowers and did a lower leg + air spring service with the correct amount of oil and grease and have never has issues since.
Thanks both - a good one to have in the mental toolbox. 👌
Interestingly, there was air trapped in the stanchion too (upon first disassembly, I noticed the hiss). This is the third time I've done a lower leg refresh on these forks, but the first time I encountered both those quirks. 🤔