Fox X2. 280psi to set sag??

apac

E*POWAH Elite World Champion
Aug 14, 2019
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I've been twiddling with my new X2 for about 4 or 5 rides. Been trying extreme differences in rebound and compression with all 4 dials. I'm not there yet, and probably won't be for another month or more... as seems to be the case with these multi adjustable high end shocks.

More to the point, I weigh 88kg and need 280psi (300psi is max) to get 30% sag on my Levo SL. 280 seems extreme.

I have looked up the tune i.d and there is no info on fox about this particular tune.

What do you think? What's your psi sag on an X2. Can I do anything about it?
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
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La Habra, California
I weigh about the same as you, but in pounds. ?
On my X2, I run closer to 25% sag, and the pressure is 200 p.s.i.

This might be total nonsense, but I've been playing with another shock on another bike, and here are my thoughts as they might apply to you. On my DPS, the recommended pressure is 225 p.s.i. But I was getting less than 20% sag at that pressure. To get more sag, I ended up lowering the pressure to 195 p.s.i., which seemed excessively far from the recommendation. At this pressure, I still wasn't using up all the travel. So I opened up the shock and replaced the big volume spacer with a small volume spacer that I turned out of chunk of plastic.

Now my sag is over 30% with the pressure at 230 p.s.i. This is not what I expected, but I concluded that the volume within the shock is so small, that taking up a lot of space can dramatically affect sag. It makes perfect sense.

Now I have a little more sag than I prefer, full travel is used on bigger hits, and the ride is plush. I think it's a little too plush, so next week I'll be installing a mid-size spacer.

My thought is that you could install more spacers in your X2, maybe max it out, and see what happens.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
1,326
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S.Wales
I weigh about the same as you, but in pounds. ?
On my X2, I run closer to 25% sag, and the pressure is 200 p.s.i.

This might be total nonsense, but I've been playing with another shock on another bike, and here are my thoughts as they might apply to you. On my DPS, the recommended pressure is 225 p.s.i. But I was getting less than 20% sag at that pressure. To get more sag, I ended up lowering the pressure to 195 p.s.i., which seemed excessively far from the recommendation. At this pressure, I still wasn't using up all the travel. So I opened up the shock and replaced the big volume spacer with a small volume spacer that I turned out of chunk of plastic.

Now my sag is over 30% with the pressure at 230 p.s.i. This is not what I expected, but I concluded that the volume within the shock is so small, that taking up a lot of space can dramatically affect sag. It makes perfect sense.

Now I have a little more sag than I prefer, full travel is used on bigger hits, and the ride is plush. I think it's a little too plush, so next week I'll be installing a mid-size spacer.

My thought is that you could install more spacers in your X2, maybe max it out, and see what happens.
If it bottoms too easy, try to put some tokens (spacers)

The shock currently has no volume tokens in it, it can take 3 which is how many came in a bag with the shock. I didn't think that adding the tokens would dramatically change the the amount of air the shock would need to achieve sag, but I could be completely wrong here. I just thought, as the tokens only change the end of the stroke, they won't effect the sag amount. But of course there will be less room for air. I will try adding the 3 tokens tomorrow.
I haven't been bottoming out , but that probably due to have 280psi in the shoak?.
By the way, due to the specialised levo's and SL's rear suspension design I think shocks tend to need more air in them.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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S.Wales
Whats the eye to eye and stroke of the shock? Whats the rear travel of the bike?

the eye to eye for a levo/levo SL is 210mm and the rear wheel travel is approx 15cm-16cm. it's approx a 1:3 ratio.
I have a 55mm stroke which equates to about 16cm
 

Mcharza

E*POWAH BOSS
Aug 10, 2018
2,614
5,368
Helsinki, Finland
And keeping the same pressure with tokens maybe eliminate bottom outs.
But try first with one token or as fox says volume spacers.
And remember that there are different thicknesses of tokens.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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When you add tokens, less air is needed to get the same sag.
Ok, I just never thought it was that dramatic a difference. Maybe just 10psi. I don't want to end up with a shock that I am not using the whole Tavel due to the ramp up from the tokens.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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S.Wales
And keeping the same pressure with tokens maybe eliminate bottom outs.
But try first with one token or as fox says volume spacers.
And remember that there are different thicknesses of tokens.
The spacers/tokens are all the same size, but you use multiples
 

Mcharza

E*POWAH BOSS
Aug 10, 2018
2,614
5,368
Helsinki, Finland
Ok, I just never thought it was that dramatic a difference. Maybe just 10psi. I don't want to end up with a shock that I am not using the whole Tavel due to the ramp up from the tokens.
First try with one and if that wont work, change the thickness of token
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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Oh sorry, you don't have Fox. Maybe RS has same thickness of tokens
The Fox X2 shock (which this is about) has same size rings...
B3438603-69C9-47B2-89A7-63525FBB2E24.jpeg
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
1,326
1,173
S.Wales
I weigh about the same as you, but in pounds. ?
On my X2, I run closer to 25% sag, and the pressure is 200 p.s.i.

This might be total nonsense, but I've been playing with another shock on another bike, and here are my thoughts as they might apply to you. On my DPS, the recommended pressure is 225 p.s.i. But I was getting less than 20% sag at that pressure. To get more sag, I ended up lowering the pressure to 195 p.s.i., which seemed excessively far from the recommendation. At this pressure, I still wasn't using up all the travel. So I opened up the shock and replaced the big volume spacer with a small volume spacer that I turned out of chunk of plastic.

Now my sag is over 30% with the pressure at 230 p.s.i. This is not what I expected, but I concluded that the volume within the shock is so small, that taking up a lot of space can dramatically affect sag. It makes perfect sense.

Now I have a little more sag than I prefer, full travel is used on bigger hits, and the ride is plush. I think it's a little too plush, so next week I'll be installing a mid-size spacer.

My thought is that you could install more spacers in your X2, maybe max it out, and see what happens.

what bike is your X2 on?
 

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
1,846
1,578
USA
I would have suggested started at 220-225 PSI for your weight on an X2. And make sure LSC and HSC are wide open to start. And the usual bit about emptying all the air, cycling the shock, then cycling the shock every 25-30 psi when refilling to equalize the chambers.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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S.Wales
I run 300psi for I think 25% or 22% sag on the stupid cascade link. Ya need 3 spacers minimum. Maybe 2 tho if you’re not jumping. Then you’ll have a lower psi. For commuting I used to run 260 with 3 spacers.
4 is the max. Which would give you the lowest psi at that sag so best tiny bump (but not small) compliance but you’d never touch bottom unless you’re doing house sized jumps
Thanks!, yeah that's the issue. It Seems like a balancing act between supple top stroke and big ramp up(maybe not using whole of stroke) OR Not using tokens and having firmer overall shock.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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I would have suggested started at 220-225 PSI for your weight on an X2. And make sure LSC and HSC are wide open to start. And the usual bit about emptying all the air, cycling the shock, then cycling the shock every 25-30 psi when refilling to equalize the chambers.
Yep, I've been super careful set up the shock... honest! Compressions wide open and slowly releasing air and making sure the shock doesn't suck in as it empties. Also slowly cycling the shock when pumping to equalise the chambers.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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S.Wales
I run 300psi for I think 25% or 22% sag on the stupid cascade link. Ya need 3 spacers minimum. Maybe 2 tho if you’re not jumping. Then you’ll have a lower psi. For commuting I used to run 260 with 3 spacers. Which would give you the lowest psi at that sag so best tiny bump (but not small) compliance but you’d never touch bottom unless you’re doing house sized jumps

I’m 96kg unless I start drinking.

I'll try 2 spacers tomorrow and see what psi I need, and then see if there's any unused stroke
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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For sure. That balancing act is why the ohlins m2 is the top rated fork. You have the dual air chambers so the first 80% is however soft you like and last 20% or so is hard to even budge if you set it up that way. Be cool if they started making air shocks like that. Depending on how rough your trail is the shock will likely feel better with at least 2 tokens. Unless you’re hitting curb sized or bigger bumps -those would feel worse
Thanks for the help. I'll report back tomorrow?
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,544
5,032
Weymouth
Im 79kg plus riding gear. X2 Float on my Whyte E180 RS has 65mm stroke. I have SAG at 30% with 230 psi.
LSR 4 HSR 3 LSC 7 HSC 5 ( all stops back from closed) . Super plush and really progressive.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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S.Wales
Im 79kg plus riding gear. X2 Float on my Whyte E180 RS has 65mm stroke. I have SAG at 30% with 230 psi.
LSR 4 HSR 3 LSC 7 HSC 5 ( all stops back from closed) . Super plush and really progressive.
Have you ever opened it up to see if you have any spacers installed?
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,544
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Weymouth
Have you ever opened it up to see if you have any spacers installed?
No sorry, never needed to. I know the shock is tuned by Whyte as Compression, Rebound and Regi ( reservoir) all medium tune. Its the Factory model.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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Went all out and added all three volume spacers this morning. Acquired sag with 250psi. 30psi lower. That's about 10psi per spacer. Havent got time to test today.
Ive left HSC wide open, and LSC just 3 clicks in from wide open ready to test.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
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I managed to get out for an hour and did a loop trail 5 or 6 times. It's a fast Section descending single track with Lots of small berms and changes in direction along with a couple of small Take offs and rolling humps.
250psi was noticeably more dampened and once I played with the rebound and compression it made for a fast and stable ride. Was fun. Definitely better. The ramp up with the 3 tokens wasn't dramatically different at the end of the stroke to the 280psi With no tokens.

just in case anyone is interested this is where I stand with the shock at present.
rider 88kg, bike levo SL. 2021 Fox X2 shock.
250psi with 3 volume spacers. 30% sag.

From closed position...
LSR 7 (16 fully open)
HSR 4 (8 fully open)
LSC 10 (16 fully open)
HSC 6 (8 fully open)

I seem to get good traction/contact with the above. Stable and not too Lively that I can't keep up!
 
Last edited:

CoreyB

Member
Sep 22, 2020
22
25
Oregon
I managed to get out for an hour and did a loop trail 5 or 6 times. It's a fast Section descending single track with Lots of small berms and changes in direction along with a couple of small Take offs and rolling humps.
250psi was noticeably more dampened and once I played with the rebound and compression it made for a fast and stable ride. Was fun. Definitely better. The ramp up with the 3 tokens wasn't dramatically different at the end of the stroke to the 280psi With no tokens.

just in case anyone is interested this is where I stand with the shock at present.
rider 88kg, bike levo SL. 2021 Fox X2 shock.
250psi with 3 volume spacers. 30% sag.

From closed position...
LSR 7 (16 fully open)
HSR 4 (8 fully open)
LSC 10 (16 fully open)
HSC 6 (8 fully open)

I seem to get good traction/contact with the above. Stable and not too Lively that I can't keep up!
I have a '21 Levo SL that I also put an X2 with a 55mm stroke onto. I weigh 93KG and am on a size Xlarge that also is mulletted and have a 170mm fork on the front. Used a Shockwiz to get my initial settings dialed in and then further dialing in based on riding. The non OEM rear shock will require more psi than the OEM to support your weight, probably based on different internal valving spec's. I was able to get 25% sag using 255psi with no added volume reducers installed.
 

Timochka69

Active member
Jan 31, 2018
143
101
Helsinki
Sag is just a number, really. Try running the shock at a bit lower pressure and add a couple tokens to avoid bottoming out.

You are much lighter than me though and the pressure you are using does sound a bit high to me. OTOH, even the pressure is just a number too, I guess. You do not really want to go above the maximum allowed, though.
 

apac

E*POWAH Elite World Champion
Aug 14, 2019
1,326
1,173
S.Wales
I have a '21 Levo SL that I also put an X2 with a 55mm stroke onto. I weigh 93KG and am on a size Xlarge that also is mulletted and have a 170mm fork on the front. Used a Shockwiz to get my initial settings dialed in and then further dialing in based on riding. The non OEM rear shock will require more psi than the OEM to support your weight, probably based on different internal valving spec's. I was able to get 25% sag using 255psi with no added volume reducers installed.
Thanks for sharing, its good for me to see what others are running to compare.
 

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