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Discussion Starter · #1 ·
Just rebuilt my Revelation U-Turn, orings looked fine, so I didn't replace any. Put it back together, and when pumped to spec with pos and neg air chambers the same (150psi for 185lbs), the fork is sitting around 135mm with U-Turn fully extended. Dropping the neg pressure to around 110psi gets the fork back to 150mm. Can't say for sure whether or not it acted like this before I pulled it apart. Whats going on?
 

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If you have the + and - chambers to close to the same PSI, the fork will 'suck down' and you wont get full travel. I believe the most popular way to set-up these dual air U-turns is to pump the + chamber to desired PSI and then add ~5-10 psi LESS in the - chamber. If you watch your fork when you are pumping up the - chamber, you can actually see the point where it begins to 'suck down' in its travel.
I just rebuilt my wifes dual air u-turn, as it was losing air from the upper chamber and thus losing full travel. It seems to be fine after the rebuild so far...

Good luck!
 

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What he said.

And 150psi sounds high. I'm the same weight and I run much less air than that. How far are you sagged in?

mk
 

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Discussion Starter · #4 ·
Just went off the pressure charts. I'm about 185-190 all geared up, 175 naked.

Seems to have normalized somehow. Felt decent around the neighborhood. Wondering if its my **** shock pump. Gonna try other ppls.
 

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The pressure charts on RS products are wrong. I am not sure where they come up with those figures. You should be setting your pressure based on sag, not on what the charts say. Aiming for around 25% sag is a good start.
 
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