Rochshox Revelation uturn issue (I think???)

Terryg

Question. On my revelations they have uturn travel from 100 to 130mm, if I go by the recommended PSI in the positive chanber I get full travel but the fork is very firm, if I release the pressure for a plusher feel I loose travel on the uturn. I should have it set on around 150psi but it was running at 110 but I was only getting around 15mm of uturn travel, is this correct??????????

Thanks in advance
Tez

nicklouse

set your sag at max travel. and adjust the neg air for feel.

you dont adjust the +ve air for plushness.

Terryg

Thanks Nick, so set the sag as per manual then adjust the plushness by the negative chamber?. I got it the other way round..durr...

Cheers
Tez

Andy!

you run the risk of letting out too much +ve air an going lower than in the -ve chamber too which is bad.

Terryg

Ok so what do you recommend?, I have set the sag but each time I take air out of the negative I loose the uturn??????. I am I missing something?, I am not a techie so any advise would be appreciated.

Cheers
Tez

Andy!

you really shouldnt be losing any U-turn.

You should have the +ve and -ve quite close to each other with the -ve a bit lower.

I find the values on the side of the fork to be a bit high so if going off them try 20-30psi lower in the +ve and then put the -ve to a bit less.

Also if might be a fault in the right hand leg that is stopping the U turn. There was a design fault in the 2007ish ones (100-130 models) were the oil from the motion control leaks and causes hydraulic lock. I had mine fixed under warranty at Fishers.

Northwind

The u-turn is a mechanical travel adjust, it absolutely shouldn't be affected by changing the air pressure.

Matt 24k

First try letting some air out of the - valve and see if your travel increases.
I set the sag with no air in the lower - valve and the U turn on full length. Next I set the sag with the + valve. I then start pump the - chamber to around half the psi in the + chamber and bounce the forks up and down before going for a - pressure within 5 psi of the + pressure.
If I go straight up on the - pressure, without bouncing the forks, I sometimes get suck down which reduces the available travel.
Not sure if this is normal but the suck sown happens on both Revelations that I have if I do not bounce them at half the desired - pressure. One is a 2008ish 100-130 non U Turn and the other is a 2010 Revelation Race U Turn 120-150 which are less than 2 weeks old.

jairaj

What year Revs?

If its 2010+ then you need to set the sag with the same pressure in +ve and -ve chambers.

There was a thread about this when they 1st came out. A few people on here including me found we got more consistency with same pressure in both cambers when setting sag.

Then once you have the sag set, you can adjust the -ve chamber for feel. The negative chamber should be with +/- 15 psi of the +ve chamber.

You should do all setting up with the U-turn at max travel setting.

Also if the forks are new, they will feel stiff to start off and will soften up after a few rides so try to get the setting roughly right and keep adjusting for the first few rides.

Terryg

They are 2007 version, I thought that the uturn was mechanical and should not effect the + & - air pressure. When I let the negative pressure out too much I loose uturn?.

Maybe I'm putting too much air in the negative chamber?

jairaj

I think even with older rock shox forks the negative camber is still supposed to be either + / - 15 psi within the positive camber.

Outside those extremes the fork may not work properly. for example on my forks if I put too much pressure in the -ve camber then it sucks the fork down into its travel.

have another read of the manual and follow the set up guide. As long as you are within the extremes the fork should work properly.