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Discussion Starter · #1 ·
In January I went for a ride in -30C. It was just an easy slow spin for an hour on roads. The next day was significantly warmer (maybe -12 to -15C) I took my bike out of my warm house and rode off a one foot drop from my deck. It is my best guess that this is the moment my shock sank to less than 50mm of travel. I didn't notice until I was about a minute into my ride. When I got home I checked the pressure in the shock. I still had the 120psi I normally leave it at. I deflated and pumped up again. It was still really low. I figured that I broke a seal so I ordered new ones from the lbs. The problem is that I live in the middle of nowhere Norway. This means that bike shops are ski shops in winter so I've been stuck playing the waiting game for a while now. I put 180psi in my shock a few months ago and usually leave it locked out. While I have about 70-80mm of travel now, it just sucks to ride. Is there an alternative fix to this? What exactly is the problem? Could I rebuild the fork with the old seals and use motor oil as a few other people in the forums have talked about doing? The ski trails here are not skiable right now and are proving to be awesome single track. I hate putting a compromised fork through the abuse.
thanks for the help,
Jesse
 

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It may be that your negative air spring is overloaded. I don't know why it happens, but on my reba solo air fork it occurs on occasion and ends up 'shortening' the fork like you described.

If you look on the bottom of the fork on the air spring side, you'll see a 5mm bolt. Take that out. Hidden underneath that bolt is a schrader value for the negative spring (there's still a negative spring in a solo air fork, it's just set automatically (or is supposed to be)). Depress that value to let the air out of the negative chamber and the fork may return to full length. Use a rag or cloth when doing so as the value can spew oil at you and your brakes under pressure, which is no fun.

I have no idea why this occurs. I first thought it was a fluke with the 'timing' of the check value that keeps the positive and negative chambers equalized, but that doesn't seem to be the case. Others have mentioned that it's due to the seal leaking, but mine has done the same thing directly after a rebuild. It seems to happen most often when I'm riding more challenging places where I'm bottoming out the fork more often, but I really don't know. One of these days I'll send it back for warranty service... For me, the 'fix' above may last anywhere from 6 weeks to a couple of days... again, makes no sense to me, but releasing the air in the negative spring gets me out of low-rider mode.
 

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Discussion Starter · #3 ·
TechniKal, THANK YOU SO MUCH! It's so rare that when someone describes an easy fix that it actually is an easy fix!
I was a little worried about the oil spraying so I removed all air from the upper chamber. Then I put a plastic bag over the fork and punched a hole in it with a sharpened spoke. I used the sharpened spoke to relieve the valve. My heart nearly kept out of my chest when my fork shot up to its full extension! You were spot on about the oil spray too! Glad I put a bag over it. Next I pumped the shock back up and found that I was still missing a few mm of travel so I released the negative chamber air again. I could hear bits of air bubbling out of the oil, which did not spray at all this time. To my surprise I gained the rest of my travel back!
Now to ride it and hope I don't come back damning you!
:)
 

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Thanks, good info! Took the damper out to release the loc spring and lost about 20 mm of travel. Confused. Followed the directions for the negative air release below the 5mm bolt and got it all back. Seems great now, just waiting for the rain to stop to get out on the trail.
 
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