i have a pair of 140mm dual air revs without the u-turn, and they just dropped around 30mm of travel for no reason, when i put my shock pump on they pissed oil out, a little out of the positive but qiute a lot of foamy oil from the negative

i've left air in the possitive and none in the negative over night and theres non escaping through, so i'd presume the seals are fine

would just a lower leg oil change solve this? and do i need new oil in the top aswell, and do i need new schrader valve internals? also any links would be great

Cheers

seal blown between +/- chambers, service or o ring kit required

you sure? air did'nt leak from the positive to the negative

too much air in neg side? if you overpump that side and underpump pos side then they will suck down…

i set them up bob on, and they were fine for 4-5 rides then sudenly lost travel and when i tried to set them up again they pissed bubbly oil out of the negative

they will poo oil out if you let air out when they are stood up, as the oil sits against the valve… so dont panic too much.

set them up again. empty ALL air out. pump up pos. then pump up neg.

what happens?

you sure? air did'nt leak from the positive to the negative

If you're shure about that, then all the seals are fine!
If the -ve was leakin from the valve, the travel would increse….

-ve needs to be pumped up with the bike upside down otherwise all the oil will pee out and it'll look foamy cos of the air pressure pushing it.

Rickos – Member
-ve needs to be pumped up with the bike upside down otherwise all the oil will pee out and it'll look foamy cos of the air pressure pushing it.

Utter rubbish

Mine pumped up fine and dandy normal way up t'other night. It's normal for them to lose a tiny bit of pressure over a few rides isn't it?

theres defo no air been transfered into the negative chamber, its the first thing i tried

i'm gona change the oil in the lower legs and see what happens

do you just put oil in the lower and non in the top?

and does puting say 7.5w oil in instead of 15w alter the spring rate or compression any?

CaptainMainwaring – Member
Rickos – Member
-ve needs to be pumped up with the bike upside down otherwise all the oil will pee out and it'll look foamy cos of the air pressure pushing it.
Utter rubbish

From TF Tuned FAQ's –

When I alter the negative air pressure in my air fork, there's oil at the valve. How can I stop this?
The oil is lube from the air chamber which collects at the bottom of the fork during use. To prevent the oil weeping, simply tip the fork upside-down before checking/altering the negative air pressure.

Why do you just say utter rubbish without explaining?

i'm gona change the oil in the lower legs and see what happens

That won't make the slightest bit of difference. All the oil in the lower leg does is slosh around and lubricate the bushes. The air cartridge is sealed away from this. If the air cartridge is running dry (No oil) you may get an air leak because of this. The onlt fix is a full strip and lube of both air chambers, which may fix it, it may not. In which case you'll need new air seals too. It's not hard or expensive to do. 🙂

you can pump them up either way up guys.

id recommend EMPTYING the neg with them upside down though… oil will come out…

what happened when you let the air out and repumped dude? as mentioned an oil change will do f all.

ive changed the oil (just for my own piece of mind) and did rivi last night, they seem fine so i'll just keep an eye on them and possibly change the seals in the air chambers and give them a complete overhall myself later on in the year

peterpoddy, do you have any good links on how to do this? and were is best to get the seals from?

thanks everybody for all you help