Long post, but I don't know what I'm talking about…

I've just put on my first ever suspension fork, a Pike 454 dual air u-turn, on my first ever mountain bike, a Blue Pig… and am having a spot of trouble setting the fork up. Any advice appreciated.

So I went through the forum, and have tried to apply PeterPoddy's procedure of setting sag, with a goal of about 35-40mm:

1. Started at the lower end of the RS table for my weight, with equal pressures in -ve and +ve. I'm around 190, so started off at 120psi (reading off the numbers off the 'dual air' table rather than 'air u-turn.' Dual air numbers are lower).
2. Checked sag, which wasn't much. 10mm maybe. Did this by gently getting on my bike and 'assuming the position' (ahem) while the bike was stationary with the rear wheel leaning up against something.
3. Got off the bike, let all air out of -ve, dropped the pressure in +ve by a bit, reset -ve to match +ve
4. Checked sag, went back to 3.

… repeated until I got down to about 80psi in each chamber, but the sag was still short, by a bit, and the fork seemed really really soft when hopping up and down the pedals around the parking lot (as if I knew… hm). So went back to 100psi, which gives me 20-30mm sag (it's not perfectly consistent). Two issues with this:

1. The fork still feels soft when hopping up on the pedals in the parking lot. The front end dives when braking.
2. 100psi seems well out of RS suggested range for my weight. Even with an optimistic table, it makes me wonder, especially since it dives.

Any advice? It's a brand new fork. Do I have to take it on a few rides and then give it another whirl? Could it be an oil level problem? Are the Ragley's angles making it harder to sag? Is my riding position all wrong? Is sag even important? Am I worrying too much?

air forks supposedly have lots of stiction when new, so maybe that ?

I agree that slack angles prob don't generate as much sag (which is what I think you're implying) – is "the postion" seated or standing ?

dunno about pike setup

Yes, definitely bounce the forks up & down a couple of times when sitting on the bike, then "assume the position". If you start with about 130psi in both chambers you probably won't be far off. Anything below about 110 for your weight is likely to be too low I think (assuming they haven't changed the 454 Pike design since my 2007 ones).

I'd just start off with what RS suggest, then ride, adjust + and – accordingly, ride, adjust, ride, adjust….etc, etc until I'm happy with it

Thanks!

It sounds like I've been too gentle getting on the bike — trying to just apply my static (sitting) weight and nothing else. Will try to give it another shot tomorrow.

And will take the shock pump on the first few rides as you suggest.

Am I worrying too much?

in a word. yes.

rockshox air take about 20hoursish riding to get good. until then i wouldn't be too bothered.

i would expect a 140mm fork to dive (a bit) under hard braking.

rockshox pressure table is shite – way too high ime.

hope that helps.

totally agree with thomthumb.
charts are too high for dual air pikes.
and you do need to rag the arse of them for a good few rides when new.
theEye..do they fell at bit sticky at the moment.
if so don,t worry this soon will pass. 😉

Are you on a slight incline too? Why prop the back wheel against something? I found out that my garden path has a slight incline after getting inconsistent sag readings on shocks and forks. Obviously really but I never thought to check for it.

In my experience most Rockshox arrive dry out of the box, as in they don't have enough oil to lubricate the lowers. My 2010 Boxxers had this issue. If you know someone technically minded it is easy to do and can make a real difference.

Also I have never found the traditional sag setting methods worked with air forks, the inevitable stiction means they don't move much leaning against a wall. Start with something slightly lower than the manual suggests, ride the bike and adjust accordingly in 5psi increments.

Like what Bagstard says. My pikes and more recently reba's both came pretty dry. The foam rings in the Reba's weren't even fully wet.

At 14st I originally ran my pikes at about 100psi until the seals loosened up a bit and I only ever ran 110psi which gave me 42mm sag (30%). So yes, the RS pressures are too high anyway IME.

The solution is to work the fork a couple of time rather than get on gentl.

if you sit on the saddle to measure and put very little force through your arms then they wont sag at all.

id only really want 30% sag when i was stood, leaning forward with weight equal over feet/hands. otherwise as soon as you stand up into this position you'll be at 40% + just when you need your forks to be working.

i find sag a bit of an odd one.

what i do is: set them up as soft as you dare really, ride around setting rebound/compression then go for a normal ride. have a band showing how much travel you have used. if its full travel then put a bit more air in. if its nowhere near full travel then let a bit out.

doesnt have to be exact. for trail centres i can run about 40psi less than the peaks…

id only really want 30% sag when i was stood, leaning forward with weight equal over feet/hands. otherwise as soon as you stand up into this position you'll be at 40% + just when you need your forks to be working.

Er, yes. That's how you measure front sag. Laden up at 'trail weight' in the attack position.

dont 'er yes' me. thats what im saying. if he's measuring sag sat down, then the measurent wont be right.

Is the motion controll/lockout on?

As above though, ride them for a couple of weeks, tweaking it 5psi either way untill it feels right. You'll probably find you need slightly more pressure after a few weeks than you did at the start and look up the rock shox service instructions as you will need to add some oil to the lowers ever few rides to keep them smooth.

I have tried setting forks up properly, and I've tried randomly tweaking them until they feel decent. I'm not sure I can tell much difference.

Just had my first air forks in years although not Pikes but 36s I think the following still counts.

When I first set them up I ran them a little too soft so I could get as much movement as possible and break the forks in as fast as I could. After a couple of rides I pumped them up by 5psi and now they are spot on.

Ignore the guide (to a certain extent) pump them up until they feel good and ride them like that. You don't have to run that much sag it is just recommend that you do. If you have come from rigid forks you will probably prefer your forks a bit on the firm side anyway.

Don't stress too much.

Thanks! it's all really helpful, I didn't know what I was doing.

Er, yes. That's how you measure front sag. Laden up at 'trail weight' in the attack position.

Don't agree at all. All the manuals, including Pikes state that you set sag in normal riding position with your weight on the saddle.

Definitely check that your compression and floodgate are dialled completely out – top of left fork, both turned anti-clockwise to their stops.

I'm about 82kg with kit including 3l of water in the CB. Run at 120-125psi +ve, 125-130 -ve which is about 10 psi less than the RS guide. Try starting at that and run them for at least 10 hours to let them bed in

I'd point out that the pressure in the manuals are wrong too.
😉

I think I got the advice from Mojo originally, but I don't really recall. Anyway works for me since about 2002.

YMMV.

I'm fairly sure that TF and MOJO recomend setting the SAG either sat upright for REAR suspension or with your weight foreward for the FORKS.

Then set it at arround 33% so that under normal riding they both have slightly less sag (arround 25%).

I just set the sag then play arround with it untill I'm happy, 1-2psi can make a difference in some forks.

One last point of advice, dont trust the shock pump to tell you what pressure WAS in there, it tells you what is in there now, if you take it off and re-attach it it takes some of the air form the fork to flow into the pump to move the dial round, as a result the shock pump always reads less than it did when you inflated them.

Cheers!

One last point of advice, dont trust the shock pump to tell you what pressure WAS in there, it tells you what is in there now, if you take it off and re-attach it it takes some of the air form the fork to flow into the pump to move the dial round, as a result the shock pump always reads less than it did when you inflated them

True, especially so for the -ve air chamber which is quite small volume – drops by about 30psi