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Problem with fork?


ozgti's picture

By ozgti - Posted on 11 July 2014

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

Hi there

I need some help. I recently had an issue where my dust wiper would pop up when I cycled the fork. To the fork to LBS and they sent it to SRAM to fix. They have apparently changed the air damper? Or something like that. Now I haven't ridden it yet but the wiper is not coming off.

The issue now is that when I cycle the fork without me on the bike it rebounds only to about 20% sag at the pressure I use to use (55 psi - i weigh about 63 kg) If I pump it up to about 90 psi it rebounds to full length. I have looked at the fork when I release the pressure and it seems almost if it gets suck down. Could it be that with the change in air damper I now have to run a higher pressure? Or is there another problem it the fork?
Something to do with the negative chamber? Fork is a 2013 Reba, solo air.

Thanks for any help

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Jonathan's picture

Did they play around with the rebound settings? Maybe they slowed down rebound which would cause the fork to come up really slowly when compressed?

If you wrote down all your settings before you sent it away make sure all settings are back to normal then try again.

spifo_clifo's picture

i have a pair of 2014 revelations (29er) that had the same issue with not extending to 100%. they sat at about 20 - 30% sag unladen with 80 - 90 psi in them.

there is actually a negative chamber in the air side (even tho they are solo air) that air pressure can get into through a dodgy seal / hair / grit / crap / etc that may get in there through the assembly process or maintenance or riding. if you remove the hex bolt from the bottom of the fork on the air side (mine is a 5mm hex) and look into the hole there will be a valve spigot (like a schrader valve).

with your bike upside down and some safety glasses on push the valve in with a small screwdriver (maybe a rag around to catch some spray oil) the air will escape and the fork will extend to 100%

mine went back to lbs three times for inspection / "repair" until i gave up and rebuilt it myself. fork is hollywood now.

before the rebuild depressing this valve every few rides seemed to keep the travel closer to the 140mm its supposed to be.

have a crack at that, it might help with small bump compliance and overall travel, plus allow you to run the lower PSI as desired.

good luck.

ozgti's picture

Went to the LBS today. Was told that because I was running a lower pressure than that recommend by Rockshox, they wouldn't look at it. All they did was pump the air up (felt like it was almost locked out) made some adjustment to the rebound and floodgate and that was it. Made me feel like an idiot. I mentioned that it didn't do that before even with the lower pressures. They kind of dismissed it. For me, it was an extremely disappointing experience, especially considering the shop had a fairly good reputation. The way I set my air pressure was looking at how much sag I was getting and how much the fork was bottoming out on my local trail. Does this sound right? I have read that technique of releasing the air from the negative chamber so I might give this a go. As for rebuilding I don't have the tools, a vice or the confidence. Like servicing a car I am concerned that if I take it to another shop for servicing, if I have a warranty claim the LBS will be even less helpful. The manager even said they are only inclined to help those who are " nice " to them.

Tuckshop's picture

Many thanks for posting this spifo_clifo. I have the Revelation 27.5 and had the same problem where the travel was down from 140mm to 120mm while the bike was unladen. I depressed the valve as you suggested and some air and a bit of oil came spluttering out ( I also recommend wearing glasses for that part!) and it's now solved the issue... the fork is fully extended.

ozgti's picture

So what is the oil that comes out from and is that going to cause a problem itself?

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