[Closed] Rockshox travel reducing dual airs, perhaps PP made a guide.

Spacers only go in the one leg, the information is in the SRAM 'Dual air' service guide. Not sure about axle to crown length changes, as far as I know it doesn't because the spacers reduce / increase the height at which the fork bottoms out.

Needle nose or circlip pliers are needed to get the O-ring out, and a 24mm socket is needed, but you might be able to do it without remocing the top cap.

Syringe is way better for injecting the oil in, as pouring it in is difficult - the oil is so viscous it won't all run out of a measuring cylinder so you only end up getting about half of what you need in.

thanks pieface i'm a little nervous to play with such an expensive item, but i want to become self sufficient within reason.

It's pretty easy if you take it nice and slow.

Let the neg air out, let the pos air out.

Undo the neg air valve at the bottom of the right leg 10mm spanner (I think) and catch the little bit of oil that'll come out.

Use the 24mm socket to undo the top cap in the right hand leg, take the last few turns slowly as there's an o-ring seal on the thread there.

Compress the fork - oil will come out of the top of the pos air chamber - click the spacers you require into place - pour the required amount of oil back in.

Lube the o-ring & carefully screw the rh leg top cap back in.

Turn the fork upside down, inject the required oil into the lower RH leg & replace the Neg air valve.

Pump up again and you're away

I did the same thing last week. The only thing I'd done before is to remove the lower legs so was a little nervous, but they're incredibly simple once you take them apart. Just take your time.

With regards to bushing removal (if you take it that far)you will need either the special tool or a home made one that i think will be quite tricky to make as it needs to be made to specific sizes.

Steveb77 - not thought of that, means you don't need to take the lowers off or remove the negative spring.

However you did forget to mention to add 5ml of oil back into the positive spring before re-assembly.

okay so i think i just need oil than i'll be set to go, off the bike till my head wound heals so plenty of time.

Pieface -> nope, just check the "pour the required amount of oil back in" bit 😉

Doing it liek that does make it dead easy. you can even do it on the bike, for pure Ghetto workshop ability

Right I only just got around to this as the frame was late arriving. So whats happening here I tried to undo the leg with the valves on but when I looked in the leg it was empty.

So I moved onto the other leg and have found this. Should I have hammered the nut at the bottom of the leg as per SRAM video. I can see where I think the spacers go. Can I just pull this red thing out to get to it.

[img] [/img]

Nahh, wrong leg mate.

That's the damping leg you've got apart there.

First put it back together!

Then you need to drop the lowers off.....etc
I did do a guide for this, but I think it's on my PC at home, not at work here. Email me (peterpoddy@googlemail.com) and I'll send it to you tonight. 🙂

1. LET ALL THE AIR OUT both +ive and -ive!

2. You have to take the lowers off (once unscrewed, the bottom of the push rods will need to be gently tapped to get then to release from the lowers).

3. Then you have to take the push rod + pistons out of the bottom of the left leg (the one the air goes in). You'll need circlip pliers for this.

4. Pop the spacer in (see service manual on RS website for the location, but basically its under the main piston head on the end of the push rod).

5. Reassemble (inc. oil in air chambers (3ml, 5wt) and lower legs (15ml, 15wt).

I have just emailed you. cheers

Not sure about axle to crown length changes, as far as I know it doesn't because the spacers reduce / increase the height at which the fork bottoms out.

if it doesn't reduce the axle to crown -what's the point in doing it?

say your bike is designed to take 120mm fork - surely if this is the case you'd just have a fork with 120mm travel but which is too long for your bike?

 

Not sure about axle to crown length changes, as far as I know it doesn't because the spacers reduce / increase the height at which the fork bottoms out.

Because the spacer sits under the piston in the air chamber, it reduces travel by not letting the fork extend to it's maximum, so a 15mm spacer fitted reduces travel by 15mm, and also reduces A to C length by 15mm 🙂

PP thanks for that bit of info

Rev fettleing here I come

best I order a space first though

Yeah I found a article on MTBR saying about the A to C. I'm looking forward to your guide PP so I can get my bike running before the weekend. Charlie it would be pointless if it didn't change the A to C, as I am doing it as I just felt to high up. Most bikes tend to be slack and long travel at the mo.

how hard are you to hit the negative valve nut? the bolt on the other leg went easily with a light tap.

😡 Right so I still have not released the valve I have hit it a number of times with my rubber mallet and it doesn't budge. In the picture below is the black bit at the top of the thread supposed to have come away with the nut? I now fully understand why tftuned have such a loyal following.

[img] [/img]

Hit it harder. Use a metal hammer as well. Rubber absorbs too much of the blow. On the valve side, leave the nut on the end of the valve to protect it: Hit the nut not the valve!
The other side is only a hollow bolt, so it matters less.

To be fair, it's usually only a sharp tap that's required, but if the forks have never been apart, it may need a bigger 'tap'..........

The tap may need to be bigger than you think. 😕

As PP says, make sure you keep the nut mostly threaded onto the end to protect the delicate valve.

Don't worry about the black bit, it's just a plastic washer.

p.s. you have let the +ive air out haven't you? That would make it difficult to release it.

yeah i did everything as described by both peterpoddy and SRAM, unfortunately it now seems as though me hitting the nut has damaged the valve threads. I'm pissed off as I was trying to save money as I'm jobless its now going to set me back 2 weeks giro money fix these 👿 Wish I'd bought U turn or a different brand.