Ok I've just got a new pair of rockshox revelation with the blackbox motion control. I've set everything up and am taking them out for their first ride tonight but in reading up on setup tips a recurring theme kept appearing. People were talking about the adjustments to the compression "gate" dial they make and from what they were saying it sounded like the gate was permanently active, whereas I'd always understood it to only be active when the fork is locked out, was I mistaken? Also I've tried adjusting the gate dial in the workshop and compressing the forks and I can't notice any difference in compression profile, is this right?

Yes , the adjustment just effects the lockout

so am I best to run the forks with the poploc engaged? and just adjust th gate as I see fit?

To be honest, I would not worry too much about the gate setting; the gate is there basically so that if you hit something hard while the fork is locked, it will temporarily unlock. Set it somewhere in the middle, and if you find that it is opening up (i.e., the fork is compressing) when pedaling hard up hill with the fork locked, then tighten it up a bit more.

(I personally came to the conclusion that the only time there is any real benefit in locking fork down is when climbing on tarmac, which I never do, so eventually removed the poploc leaver altogether. But someone will undoubtedly come along shortly to say that the pop lock is the most useful, indeed, crucial, part of the fork, and that you need to set the gate with the utmost care 🙂 )

I'm with tf on this one, most especially the first paragraph.

I had poplock on a set of pikes, removed it too, waste of time for most people i reckon, unless you don't want to use your suspension.

The floodgate can work when not locked out too (despite what the manual says). This guy has some interesting things to say:
clicky

ok that makes an interesting read. SO do I take it that the people that actually use the poploc adjust the "lockout" dial by small amounts depending on what the trail is like? As my forks came with pushloc it would make this just a touch difficult

Same here, poplock removed on some Revs!

Agree with tf, Ambrose and rs. Had Pikes for 2 years and have always set the floodgate (same thing) to off. Always have the compression damping set to zero as well.

Go with Kapusta's post that specializedneeds has linked to and you won't go far wrong.

Well I took them out for their first ride today, and wow they are pretty damn sweet, the sensitivity of the forks on small bumps is incredible- I was getting no pain in the pains or wrists from downhills that normally make me ache and the U-Turn actually was really useful, they climb alot better when wound down and I was pleasantly surprised as to how active they still were.

One question though, I seemed to go through the travel quite a lot- I know I'm fairly heavy on the old suspension- my rear shock will testify to that but I was surprised how close I came to bottoming them out, I'm running about 25mm of sag on them, am I running them with slightly too much sag/ not enough pressure or is it more likely my riding style?

I run about 10psi less in the negative chamber of my Teams, I found the same, that they used their travel a little bit easily. Just a matter of taste of course, I'm sure a lot of people find that plushness really nice and on fast rough trails it was great, but I find it a wee bit disconcerting on steeper techy stuff so tuned it out with the negative pressure. The downside of that is that the fork's a bit less plush but that's a worthwhile trade IMO.

Right ok, so if I run the negative pressure lightly lower then it'll stiffen it up, Its bloody confusing this set up malarky as there are so many different suggestions. What sag do people tend to find works well for agressive xc?

Try using the compression damping rather than setting less negative pressure.

I use the Gate Valve as a form of compression dampening and have the lock out on all the time. This does mean that I don't have a 'proper' lock out but then again it's not a road bike and I'm not in le Tour.

ETA: The forks are a set of Push'd Pike Dual Airs. I did it after speaking to TFTuned and they suggested I try it.