A place for airshox data.

[Captain Ron]

Let's see whatcha got.

I'll post pretty pictures in place of real tech.



--ron

 

[XJ_ranger]

So...

the Fox 2.5 and 2.0 airshocks take a 1/2" bolt which means that you need a 3/4" wrench and a 3/4" socket for the impact...


'its not summer at Liracon unless ive puled a few airshocks!'

 

[Captain Ron]

Ok, just for the record...

19mm Bryan....



--ron

 

[Jump This]

My Fox shocks came with an assortment of eye inserts to run metric or standard hardware!
I can go both ways now...

 

[Weasel]

If you don't like the unloading Fox has two different pistons for their air shocks. One has bleed holes, use these. Should help quite a bit. Walker Evans air shocks have bleed holes in their standard piston. That why the Walkers handle of-camber better and don't unload as much. Walkers pistons are linear, Fox's are a non-linear, digressive IIRC. Oil Level is easy, add oil till they don't bottom out. N2 pressure controls the ride height. Zip ties around the shock bodies help determine how far your shaft is compressing before bottoming out. Walkers are lighter then the Foxs. In general the rebound has more damping the compression. What else do you want to know?

 

[Goatman]

Do they work the same at all altitudes?

 

[Paul S]

The single bleed piston that works so well is actually a Fox Nitro bumpstop piston, not a single bleed shock piston.

Ron, I took my bumps & shocks apart last night & confirmed that my 2" shocks do have bump stop pistons.

From last week I found the following with the 2" rears:
300cc's & ? PSI: worked really well. Very smooth & bottomed only when hit hard.
I added 10cc's & set the PSI to 180 to take out the little bottoming I had. The ride got a little harsh & it bottomed easier.
I added another 10cc's at 180 PSI thinking this would help. Now at 320cc & 180 PSI it bottomed easily on the trail & on the fast & the ride was very harsh.
My conclusion is that the oil controls the dampning, while the Nitro controls the spring rate.
So, I will go back down to 300cc's & increase the PSI to approximately 215, which is what Ron has & is very smooth without bottoming.

Front 2.5's with 440cc's & 210 PSI work great. I don't think they ever bottom, but they are very smooth.
I'm going to take 10cc's out to soften the ride a little bit, we'll see how it goes.

Still don't know which end, if either, I'll need the bumps on.

P

 

[Captain Ron]

I'll get some piston pics up in a few hours.

--ron

 

[xDUMPTRUCKx]

thank you guys for doing all the research and spending all the time and nitrogen on getting the numbers that work so people like me can set up air shocks in a day

 

[Dirk Pitt]

Why don't you guys that have them post up your sprung and unsprung weights, front and rear to establish some relativity???

 

[Paul S]

Why don't you guys that have them post up your sprung and unsprung weights, front and rear to establish some relativity???

I'm new to airs, but from my limited experience I think the most useful tool for anyone is to know what does what. Once you know what does what it's very simple to make changes.
Takes about 1 minute to add Nitro.
About 5 minutes to add oil.
About 20 minutes to reduce oil.
Once we establish what does what, you could bolt 'um on as is from the factory & tune from there.

P

 

[Captain Ron]

2.5 Piston, double bleed. The bleeds are .093" dia.

The bleeds pass though the rebound ports. What looks like 2 additional bleeds are not drilled though, just spotted.

This is the single bleed. .065" dia.

2.5 piston, compression side.

Rebound side.

The rebound and compression ports are the same feature size on both pistons. The are the same piston, except for the bleeds. Rebound is a round port...

Compression is a significantly larger obround port...

--ron

 

[Captain Ron]

2.0 piston, double bleed, .069" dia ports.

Single bleed. Same dia.

Rebound side.

Compression side.

Compression port obround feature.

Rebound port, round feature.

2.0 valving specs. The "S" is where they were at from the factory, the arrow is what I ran last week.

Same for the 2.5's.

Fun with shims.

--ron

 

[XJ_ranger]

make sure to have the shock at full extension when adding nitrogen...

and when removing the shock

Fox 2.5 spacers, schrader valve removed to dump all oil and nitrogen -

pumped out -

 

[Paul S]

Just back from 3 days in JV & I think I've got all 4 airs dialed in as good as they'll get, or close to it.

Fronts worked well form the beginning, but I took 10cc's out to soften them up a tad, which worked great. They ride great in all conditions & never bottom.

I took about 25cc's out of the rear & increase the psi by about 40. This puts them at 305cc's & about 220psi. I can't believe the difference this made. They're are silky smooth & only bottomed 3 times in 3 days, & only lightly at that.

P

 

[Captain Ron]

Just back from 3 days in JV & I think I've got all 4 airs dialed in as good as they'll get, or close to it.

Fronts worked well form the beginning, but I took 10cc's out to soften them up a tad, which worked great. They ride great in all conditions & never bottom.

I took about 25cc's out of the rear & increase the psi by about 40. This puts them at 305cc's & about 220psi. I can't believe the difference this made. They're are silky smooth & only bottomed 3 times in 3 days, & only lightly at that.

P

I hear God only bottomed out 3 times, in the first 6 days, surely you can do better than that.

Without geometric tolerancing, your data is irrelevant.

Please post current info only.

Thanks.



--ron

 

[Paul S]

I hear God only bottomed out 3 times, in the first 6 days, surely you can do better than that.

Without geometric tolerancing, your data is irrelevant.

Please post current info only.

Thanks.



--ron

Alright smarta$$, ? for ya: now that I've got the spring rate where I want it, how do I change the ride height without screwing everything up?
I've got about 7.5" of rear shaft at ride hight, I want to lower it to a little less than 7", any ideas?

P

 

[Captain Ron]

Alright smarta$$, ? for ya: now that I've got the spring rate where I want it, how do I change the ride height without screwing everything up?
I've got about 7.5" of rear shaft at ride hight, I want to lower it to a little less than 7", any ideas?

P

This is where I think I was going in the wrong direction the last height adjustment I made. I went down about a half an inch like you want to, added oil, and reduced pressure. I'd been working that trend for a few adjustments, and the front started bottoming.

--ron

 

[Goatman]

I've never messed with these, but from a total lack of knowledge perspective it would seem that if you removed oil and kept the pressure the same that the ride height would be lower.

Or do you have to mess with both and tune them over again?

 

[Captain Ron]

You can add or remove pressure for ride height, but it comes with a change in rate.

If it's a small change in pressure, no big deal. The problem is that it's rarely a small change, smaller than 5 psi. 10 psi is alot of change and has a noticable impact.

It's a treadmill. When you gettin on?

--ron