I've just serviced Juans forks. No problems doing it, I just took them apart, removed the air and damping cartridges, relubed them and changed the damping oil, then put them all backtogether again. I DID NOT open up the Doppio air cartidge

Anyway, I've got hold of an air adaptor so I can pump them back up, and had a look on the net for set up advice, but I can't get anyhwhere near the given pressures for my weight as the spring is basically rock hard at those pressures. I think I have around 50psi in them at the minute

AND they have the harshest top-out clunk you can imagine! I've slowed the rebound down which has no effect on the clunk
When Juan gave them to me they were sitting right down into their travel at maybe 100-120mm, so they didn't top out. I've now got the full 150mm showing.

They don't feel too bad to ride, a lot smoother than before, but something isn't right somewhere.

Any ideas?

PP, I had a set of these and they were notoriously difficult to set up.

There's loads of info here though:-

AM1 SL

And Here: –

AM1 SL

The pressures they quote are MUCH too high- I ran no pressure in the PAR and not a lot in the others.

As for the topout- sounds like oil height issue. Maybe add more oil?

As for the topout- sounds like oil height issue. Maybe add more oil?

To what?

Lubricating oil in each leg, and the damper cartridge is full and seems to be working fine. There's nowhere to add oil that will stop the clunk methinks……

KS – After reading that link (Well, most of it) it doesn't really help but there is mention that the fork should sit into it's travel on negative pressure a bit, which was my thought too. I just can't get it to do that!

As Spokes says – 50psi is MUCH too high – 35psi would be nearer the mark.

This is the best guide I have found. (It's a PDF)

I'll be honest, I don't know. I know mine pissed oil out of the top of the non-lockout side leg and then started topping out.

Mr R – I've already read that PDF. It'd basically as clear as mud IMO. It doesn't really say HOW to set them up, just badly worded explanations of what each valve does.
But thanks for the link 🙂

KS – Just read through your 2nd link. It seems the given pressures are way out, which figures!

From what I remember:-

Basically the PAR chamber controls the bottom out resistance and the mainchamber effects the air spring weight, it's a balance : –

1. Good feeling fork but with Top Out = More pressure in PAR vs Main Chamber

or

2. Linear, sometimes stiff feeling fork = Less Pressure in PAR More in main chamber but no top out (Fork sits in it's travel).

Just a note too, always pressure the PAR 1st and then set the main chamber air! This applies for both options.

I set mine up with pressures as per the sticker on the fork leg and they work fine. I always pump the higher pressure section (lower chamber) up first. They don't sag much in a seated position but also don't dive or bottom out.

pp as spokes and rusty the pressures in the manual are way to high

try about 6 psi in the PAR
25 – 35 in the positive chambers depending on the amount of Pies that Juan has consummed recently…

t1000, did you mean 60 or 6 in the PAR?

KS – Now we're getting somewhere, cheers for the tips! 🙂

Yes I run mine at about 6 psi

I'll post the full set of settings when I get home, I run the SL1's on v low pressures despite being 14 stone-ish on a 456 with about 20mm of sag I don't use the neg spring to reduce the static height (personal preference)

Same as T1000 with lowish settings – for me positive just under 30, PAR about 8-10. Also agree with the neg setting.

Cheers guys, I'll give it a go, many thanks! 😀

So I tried it.

The positive and negative chambers just equalize in pressure, so I'm guessing something is rather wrong with them then?

PP I should have some pressure setup guidance from TF when I had them serviced about 3 yrs ago

I'm guessing that Juan's don't like running at low pressures or could be a split bladder?

Still worth trying at a higher pressure to see if they'll maintain a differential between the neg and pos chambers 9that should prove if somthing nasty is going on inside)

PP if they equalize then there is an issue, fortunately for you I have found this service guide 😀 Looks like it may be simple as an O ring.

AM1 SL Service Guide