Fox Air shocks

[blt2krl]

Well I have buddie in my 4x4 club that has these on a scout/buggie. He has the 2.0. I was thinking as soon as my rear springs start to give up the ghost, I will 4 link the rear and use a set of 2.5 fox air shocks instead of coil overs or simple coils. Install would be simples and tunning seems to be straight foreward. Lets discuss this. Anyone have any pro's vs con's? I have read billavistas write up on Pirate and he seems to love the 2.0 as well. I would think a 2.5 would be able to hold the weight of a waggy.
http://66.195.16.160/~dave5150/shop/t_182.jpg

[Frank in Norway]

Just remember that air shock don't have any resistance when extended. It can be scary or lead to a roll-over when off-cambered.
I personally would not use air-shocks on anything that's going to see terrain.

[Desert Beast]

Originally posted by Frank in Norway:
Just remember that air shock don't have any resistance when extended. It can be scary or lead to a roll-over when off-cambered.
I personally would not use air-shocks on anything that's going to see terrain.Can you elaborate? When you say no resistance when extended, is that while extending? So no dampening on the extension stroke.

As for the shocks I have heard that the 2.0s aren’t quite up to the task of a full size rig. the 2.5's might be though. Haven’t done any research on the 2.5's.

Secondly im not a big fan on them simply for reliability reasons. I’m not saying that they’re not reliable but in the event of a failure you have no redundancy for the suspension. If you blow a seal or the Schrader breaks or whatever, and you loose air pressure you are sol.
Now w/ a coil-over or just coils, it’s quite a bit harder to break a coil, and if you loose pressure on a coil over you can still get off the trail w/ it.

How much are the 2.5's? Much difference between those and a coil over?

[blt2krl]

Originally posted by Frank in Norway:
Just remember that air shock don't have any resistance when extended. It can be scary or lead to a roll-over when off-cambered.
I personally would not use air-shocks on anything that's going to see terrain.That is why most how run that setup in a vehicle that is four linked front and rear also run an anit rock setup. With that setup there are no issues. I plan on keeping leafs up front still after I four link the rear. In this type of setup I have not heard on any problems that you mention. That doesn't mean there aren't some experiences out there.

[blt2krl]

Originally posted by Desert Beast:
</font><blockquote>quote:</font><hr />Originally posted by Frank in Norway:
Just remember that air shock don't have any resistance when extended. It can be scary or lead to a roll-over when off-cambered.
I personally would not use air-shocks on anything that's going to see terrain.Can you elaborate? When you say no resistance when extended, is that while extending? So no dampening on the extension stroke.

As for the shocks I have heard that the 2.0s aren’t quite up to the task of a full size rig. the 2.5's might be though. Haven’t done any research on the 2.5's.

Secondly im not a big fan on them simply for reliability reasons. I’m not saying that they’re not reliable but in the event of a failure you have no redundancy for the suspension. If you blow a seal or the Schrader breaks or whatever, and you loose air pressure you are sol.
Now w/ a coil-over or just coils, it’s quite a bit harder to break a coil, and if you loose pressure on a coil over you can still get off the trail w/ it.

How much are the 2.5's? Much difference between those and a coil over?</font>[/QUOTE]You bring up some good points DB. The 2.5 Fox coil over is 495 ea plus springs. The 2.5 air shock is 300 ea. Now coil springs would be cheaper for sure but then you have to fab up spring buckets where as air shocks it is just a matter of welding some tabs where you want. Good points keep them coming.

[Stuka]

Coil overs dont need spring buckets. The have a pin on each end. Standard coils use spring buckets (like the front of a dodge pickup for instance). But the point of a coil-over-shock is that the shock is inside the coil, and the coil mount is a single pin on each end.

[Frank in Norway]

I mean that the air pressure in a air-shock is only on the pressure side. There is nothing dampening when the shock extends. More or less like a coil spring setup with coil fixture only on one end of the coil and with no shocks.

A sway-bar setup would work. I still think coil-overs or coils and a separate shock would be much better off-road.

[RickyB]

Air shocks will also unload on you in an off camber or steep position. That is why the rock buggies with air shocks use a winch to compress the suspension. Imagine you are trying to ease down a ledge and you are at the borberline of tipping, and all of a sudden your rear air shocks unload and actually push you further into the pucker. Not a good thing.

On the other hand, you get major flex with them.

[rockcandy]

Most of the negative statements I have seen thus far are such BS. I have been on tons of trails with folks running the Fox Air shocks. They are as stable as any coilover in my opinion and lighter. Comp and trail buggies run winches to the axle to keep any suspension from unloading during climbs/descents. I've seen it on leafs just as much as I have seen it on coils/air/coilovers. I say go for it! Some people need to brush up on what top comp guys are running...it's not coilovers ;) No, 4 wheeler/4 wheel and offroad magazine don't count for sources. If you are at the point of having air shocks on your rig, there is no reason you shouldn't be prepared. Throw in a seal kit and a new schraeder valve in the tool box if your worried about failure!

[Stuka]

what frank said is correct. As the shock gets more expanded, it looses its dampening, because the air pressure inside drops. This is what causes the tipsy feeling as they get expanded out more. With a coil over, there is always has outwards pressure being exerted if adjusted correctly. The air shocks loose pressure as they go out, so the 'spring rate' changes more drastically. If you look at most pro buggies that run air shocks, they have very low centers of gravity, they arent a lifted up full size truck with a high center of gravity.

[blt2krl]

Okay no on the unloading that some are talking about. The fellow in my club is running them front and rear in a 4 link configuration. He told me that were people go wrong is just running the shocks with no anti rock setup. He has talked to pro that run that setup on comp buggies. I can tell you I watched him run Upper Helldarado and Coyote Canyon in Moab and he never once had an issue with unloading. RC do you know of any setups with leafs up front and air shock/ 4 link out back. Looking for some real life experiences with this setup. Good disscussion lets keep it going.

[Frank in Norway]

That was my point. You can't run them succesfully without some sort of sway-bar.

[Desert Beast]

good points, but comparing our rigs to comp rigs is like apples and oranges. (now remember I haven’t read about the 2.5's) but I’ve talked to people that run the 2.0s and say that the 2.0s would be a bit small for a full size rig.
just b/c the comp guys run something doesn’t mean that its right for a fullsize rig. I wouldn’t put a VW motor in my jeep. nor would i do everything i can to reduce weight.
im not saying that they are bad but the whole comp comparison is over used (i think)

rockcandy, don’t forget the nitrogen setup that you’d need for a trail fix also.

[blt2krl]

Originally posted by Frank in Norway:
That was my point. You can't run them succesfully without some sort of sway-bar.Gotcha, thanks for input Frank. Any other issues?

[KYJ10]

I was told by the guys at poly that coilovers are better, they just cost twice as much. Never asked why, but was told the airs were a good product.

I was gonna order my 2.0 fox's next week, cause im like a feather in the rear. I But I found a set of used coilovers, that have one trip on them, and look to have about the right spring rates. Lucked into them for 1/2 what they sell for, and it's cheaper than the two fox's, so I pretty sure Im gonna run the coilovers.

thats all I know, and it's not much!

[orangecherokee]

The last comp I went to I notcied a lot of rigs going with air shocks. It took me a minute to figure out what was going on but once I did it was clear. Lots of rigs were using limiting straps instead of winches. not that winches weren't used but you get the idea.

DB, you wouldn't necessarily need Nitrogen would you? you would later on to fix it permenantly but not to limp off the trail. i know the reason behind using nitrogen but as a necessity, I don't think it would be needed.

[Stuka]

You could use dry air (dryer on compressor) to get off the trail I think, the shock would just change rates as it got warm.

[orangecherokee]

Originally posted by Stuka:
You could use dry air (dryer on compressor) to get off the trail I think, the shock would just change rates as it got warm.yeah, i understand the nitrogen use (just like in nascar) but compressor air would do good in a pinch.

[rockjeep44]

This argument can go on and on because you have haters on either side but really there is one bottom line. If you have the money buy coilovers, there is no reason not to. If you don't have the budget but still want a similar performance to coilovers get air shocks. Yea they have their negatives but for the price they are pretty darn good. I personally would run coilovers because of their tunability AND reliability but it all comes down to $$$. How much do you want to spend? Simple as that.

[ September 19, 2005, 08:20 AM: Message edited by: rockjeep44 ]

[rockcandy]

Originally posted by blt2krl:
... RC do you know of any setups with leafs up front and air shock/ 4 link out back. Looking for some real life experiences with this setup. Good disscussion lets keep it going.My friend that I wheel with all the time has the fox shocks out back with leafs in front. Works awesome!

[Desert Beast]

Originally posted by rockjeep44:
This argument can go on and on because you have haters on either side but really there is one bottom line. If you have the money buy coilovers, there is no reason not to. If you don't have the budget but still want a similar performance to coilovers get air shocks. Yea they have their negatives but for the price they are pretty darn good. I personally would run coilovers because of their tunability AND reliability but it all comes down to $$$. How much do you want to spend? Simple as that.good point man,
like the old hot rodders say,
"speed costs money, how fast do you want to go?"

[jode]

Just a couple points from a wannabe mall crawler:

I have buddy who runs leafs front/4 link rear with a regular coil spring/shock config - not the same by any means, but just a thought - he finds it difficult to balance the supaflex of the 4 link/coils with the so-so flex of the leafs. It just doesn't balance out well.

Some people here seem to need to understand that spring damping and spring rate are two totally separate things even if the air shock does them both. I find it INCREDIBLY hard to believe (although I have no data on this) that these airshocks have no extension damping.
Yes, the spring rate will drop as they extend, but I just can't bring myself to believe that they have no damping on the extension stroke...please prove me wrong ;)

[Stuka]

I am not sure on the dampening bit. I would need to see a cross cut of the cylinder. I am sure there is some dampening, but the recoil would be far stronger than the recoil.

[Frank in Norway]

The air shocks have some rebound dampening, but not very much. It's like a rig with very soft coil or leaf spring.
You could get used to it, but they'll work much better (safer) with a good swaybar setup.

Another thing is that Fox says max 1000lbs pr shock. Our rigs may be a little too heavy, but I don't know.

Best things about airshocks is the price and the fact that they are easier to install in a custom suspension setup.

There are a good thread and a tech writeup over at pirate:

http://www.pirate4x4.com/forum/showthread.php?t=172649&page=1&pp=30&highlight=shocks+rebound+dampening

http://www.pirate4x4.com/tech/billavista/PR-Airshox/

[orangecherokee]

Another thing is that Fox says max 1000lbs pr shock. Our rigs may be a little too heavy, but I don't know.yeah but you have to realize that Paul cut half of his body off already and what's left is tube. i think it would be silly to tell him to weigh it beforehand b/c i figure he already knows that.

[rockjeep44]

Originally posted by Frank in Norway:
Another thing is that Fox says max 1000lbs pr shock. Our rigs may be a little too heavy, but I don't know.Actually the 2.5s that Fox has now carry double the load that the 2.0s carried.

Originally posted by jode:
I have buddy who runs leafs front/4 link rear with a regular coil spring/shock config - not the same by any means, but just a thought - he finds it difficult to balance the supaflex of the 4 link/coils with the so-so flex of the leafs. It just doesn't balance out well.I don't run this setup but I've seen it run and I like it as a capable, flexy, budget suspension setup for several reasons. First, the leaf front provides stability to the rig and is not overly flexy. The rear will do most of the flexing but really that is fine. Second, if you can get your front end over the obstacle at hand you are golden. With your flexy, linked rear all you have to do is hammer down and she'll walk right up. No axlewrap and the rear will just plant and launch.
-Andrew

[rockjeep44]

Originally posted by Stuka:
but the recoil would be far stronger than the recoil.Really? ;)

[Stuka]

erm... thats what I get for posting when I am tired tongue.gif

Allow me to rephrase.

The rebound would be far stronger than the bound. Since the shock and lifting part appear to be built in as one (correct me if I am wrong) the dampening would be lopsided. If somebody ran standard shocks along side of them, then that wouldent be an issue. It may not be an issue as is anyways, since its not like they will be trying for lap times. But it may/may not play a roll in wheel hop.

[KYJ10]

Hell my coilover deal fell through, so Im gonna order my airs next week. Hopefully I will be able to give you a first hand observation in a few. I think Im going with the 18" 2.0. Im not gonna have more than 400-600lbs on my corners, so I will be fine. Oy yea, Paul, got your package, thanks so much, I really owe you one! Dennis

[blt2krl]

Originally posted by KYJ10:
Hell my coilover deal fell through, so Im gonna order my airs next week. Hopefully I will be able to give you a first hand observation in a few. I think Im going with the 18" 2.0. Im not gonna have more than 400-600lbs on my corners, so I will be fine. Oy yea, Paul, got your package, thanks so much, I really owe you one! DennisCan't wait for the report on the AIr Shocks. Also glad you got the package. I hope they will work for ya.

[jode]

Originally posted by Stuka:
The rebound would be far stronger than the bound. Not sure what your logic is for saying this? :confused:

Air shocks are not new - for example, on Mt bikes, they use air shocks often and there is adjustable damping on both extension and compression according to the design of the shock. As you (or someone else) stated, it all depends on the design of the shock. ;)

[Stuka]

A suspension has two actions, bound and rebound. Bound is when it is compressed, rebound is the action of expanding back to its rest state. With an air shock such as the fox, the air is holding up the vehicle. So the rebound is going to be charged, while the bound wont be (unless the air shock is setup to have equal pressure on each side, and isrest state is centered, not expanded). This results in uneven dampening, which will result is a bouncy ride, unless some form of dapening is added. But I cannot say for sure that the fox will indeed work this way, as I dont know the internal design.

[jode]

Right, you are talking about simple spring action excluding any damping characteristics. I find it highly unlikely that Fox sells a shock in which the rebound damping is not tuned to counter the effects you describe. It would be a worthless shock.

[blt2krl]

The shocks are nitrogen and oil combo. I copied and pasted this off Billa vista tech article on pirate.

Advantages:

Weight - each unit, comprising "spring" and very high quality rebuildable shock weighs only six (6) lbs!!!
Compact size - the entire unit has an OD of only 2.0" making them extremely easy to fit.
Adjustability - by varying initial nitrogen pressure ("spring rate" and ride height) and the volume of oil in the shock (spring curve progression), along with adjustable valving - they offer a broad range of adjustability.
Price - at a suggested retail price (as of this writing) of approximately $225 US they compare very favourably with a high quality spring and shock absorber setup and are quite a bit more economical than traditional dual or triple-rate coil-overs.
Ease of mounting - Great flexibility in mounting options and configurations is afforded by the fact that each end of the unit mounts with a high quality Aurora brand spherical bearing and a single 1/2" bolt.
Disadvantages:

Requirement for high pressure nitrogen source. - this is more of a neutral, as traditional springs obviously don't require one - but then again aren't adjustable either. Note that this requirement is true of both Airshox and coil-overs as coil-overs also need to be periodically charged with hp nitrogen.
Price - compared to junkyard springs and shocks, these are obviously more expensive, but then we're hardly comparing apples to apples.
Affect of Heat - It is theoretically possible to heat the shocks up to the point that there will be a detrimental effect on the volume/pressure of nitrogen with which they are charged, potentially altering the spring rate/ride height during use. Whether my practical experience bears this out you will have to read on to find out! Note that the magnitude of ambient temperature changes (for example, seasonal changes in outside temperature) have neither a theoretical nor practical effect on the shocks.
Weight carrying capacity - maximum capacity for the shocks to support is 1000 lbs per corner of sprung weight. That equals about a maximum of 5000lbs GVW, depending on vehicle. They generally perform best on lighter vehicles.
Natural roll resistance - similar to softly sprung coil-over setups, these shocks offer very little natural roll resistance. Not a problem for a trail-only rig but may be an issue for a daily driver. Easily fixed with a sway bar though.

[blt2krl]

Here is a great cut away.
http://www.pirate4x4.com/tech/billavista/PR-Airshox/!%20internal%20medium.jpg

[Stuka]

Aha, now that I see te cut away I can see better how they work. The oil/N2 combo helps prevent rate changes as they expand and contract, and should help give more dampening.

[ September 20, 2005, 02:33 PM: Message edited by: Stuka ]

[orangecherokee]

but couldn't excessive heat and movement cause cavitation?

[Stuka]

Yeah it could, as well as heat. I wouldent use them for baja racing. But most cralers dont see that kind of movement in their suspension.

[rockcandy]

Give me a little bit here and I'll post pics of my friends setup and you'll get a good idea on how leafs/fox shocks can be balanced. All these naysayers and they've never seen it in real life. Just on the intraweb.

[Stuka]

Hey, I am not neighsaying anything. I am just giving an opinion. Not once have i said "they wont work, dont use them". I am just throwing out ideas, which I thought was what paul had asked for.

[rockcandy]

Originally posted by Stuka:
Hey, I am not neighsaying anything. I am just giving an opinion. Not once have i said "they wont work, dont use them". I am just throwing out ideas, which I thought was what paul had asked for.I know I know smile.gif Just with everyone saying they'll dump you over and stuff to me is just garbage. I just think someone should know how something works before bagging it.

http://www.fullsizejeeps.com/jeeps/files/AZ_FSJers/foxshox1.JPG

http://www.fullsizejeeps.com/jeeps/files/AZ_FSJers/foxshox2.jpg

http://www.fullsizejeeps.com/jeeps/files/AZ_FSJers/foxshox3.jpg

[ September 20, 2005, 09:49 PM: Message edited by: rockcandy ]

[rockcandy]

I have to say the Fox shocks also work very well at high speeds. Flying through the desert with lots of whoops and ruts, it was night and day difference going from leafs to Air Shocks. I am talking about maybe 5 minutes of hard abuse at a time so I can't comment on extended periods of desert running. Although I dig coilovers, a lot, I would find something else to spend the additional $600 it will cost you to run coilovers, compared to the Fox shox. If money is no object or you are going for bling have at the coilovers.

[rockjeep44]

Air Shocks may be night and day over leafs but Coilovers are night and day over Air Shocks. Here is a quote from Billavista comparing Air Shocks to Coilovers after he had run both...

I've run both on the same rig in the same terrain.

Airshox advantages:
price
low weight
simplicity (not in understanding all the physics, but because your adjustments are limited)

Coilover advantages:
Massive adjustability (can also mean complexity and frustration tho)
Ability to really haul *** - I found the airshox better than soft leafs, but with coilovers the dirtbikers can't keep up!
Ability to handle much broader range of weights of the rig.

Airshox are an awesome product / option / addition to the market, but they in no way replace coil-overs.

[orangecherokee]

i'm sorry but the caption should be....

"The kick is up.......and GOOOOODDDDDD!!
http://www.fullsizejeeps.com/jeeps/files/AZ_FSJers/foxshox3.jpg

[blt2krl]

Originally posted by rockjeep44:
Air Shocks may be night and day over leafs but Coilovers are night and day over Air Shocks. Here is a quote from Billavista comparing Air Shocks to Coilovers after he had run both...

I've run both on the same rig in the same terrain.

Airshox advantages:
price
low weight
simplicity (not in understanding all the physics, but because your adjustments are limited)

Coilover advantages:
Massive adjustability (can also mean complexity and frustration tho)
Ability to really haul *** - I found the airshox better than soft leafs, but with coilovers the dirtbikers can't keep up!
Ability to handle much broader range of weights of the rig.

Airshox are an awesome product / option / addition to the market, but they in no way replace coil-overs.I think to think air shocks are better than a coilover is defiently inccorect thinking. It really comes down to what you said earlier, how much money do you have to spend.

[blt2krl]

RC, thanks for the picks. Looks like a killer rig.

[KYJ10]

I have been told that the SAWS and Fox airs are even as far as quality and durabilty. Now that being said, I thought I would pass this along to you. I forget the name of the company in UT, but they are running the 18" SAWS for $195. By far the best price I have seen. I really wanted the fox , believe it or not, because of the blue colored ends. But saving about $30 a shock, I can deal with the red! Dennis

[KYJ10]

ooops, heres the number 435-752-4272