Review: DHX Air 5.0 fitted with Float RP3 Air Sleeve.

[Netwelle]

This is an initial review of a mod I found on another forum. If you are having issues bottoming out the Fox DHX Air this may help you.

Here is a link to the Mod.

http://forums.mtbr.com/showthread.php?t=182747

I installed the sleeve and aired it up to take it for a cruise. Just riding around my house I noticed a huge difference. The bottom out seems to be a lot more forgiving. I tried to compress the shock as much as I could in a few situations, the compression felt tighter. I set the air chambers to 120 on the piggy back, and 180 on the main chamber. It feels pretty stiff but I may need to play with it a bit. Here are some pictures of before and after.

Original Setup:

http://www.dirt-fix.com/before.jpg

Float RP3 Float sleeve setup:

http://www.dirt-fix.com/after.jpg

[Netwelle]

Well I just got back from my first ride.

It was just what the doctor ordered. It was a ten mile ride the first 40 minutes was climbing up switchbacks. With the propedal all the way on the bike climbed like a champ. There seemed to be much less bob then I remember. For the downhill and remaining part of the ride I had the propedal mostly off. I was able to jump and compress in hard turn much better. the shock did not bottom out once the whole ride. I am stoked. During the first bit of downhill I had to adjust the rebound down. It was too progressive. I turned it down four clicks and the rest of the ride went perfect.

I weigh 180+ with all my gear and a full camelback. This modification seems to be the ticket if you are a heavier rider. I suggest it to anyone who is having bottom out problems. You can't go wrong for $40 in parts.

matt

[Lelandjt]

So you wanted a more progresive spring rate but you run you shock in the more linear mount hole? Why?

[Netwelle]

Dude from Breck. Sorry maybe progressive is not the right word I should have used. I have the shock in the front hole because that is where it needs to be. The back hole will leave the head tube too slack.(from what I am told) I asked the kona techs on their forums about this before I did the project.

All I was trying to say was that my rebound was too fast. I had to tone it down a notch. I guess I should not have used "progressive" to describe it.

Although I could be wrong completely. What kind of feel would I get if I had the shock in the back hole? I was advised against it, but I a willing to try it if I can get a good argument for it.


On another note. How much snow do you guys have? It dumped here in vail yesterday and rained down valley where I live in Eagle. I am going to escape to fruita this weekend. I can not handle this weather anymore.

[Lelandjt]

Don't know how much snow Breck got cuz I'm in the middle of my Maui spring fling. Just kiteboarding and surfing. As for the mount holes, I didn't think it made a geo change. You can confirm if it changes geo by moving the shock eyelet between the two holes and watching the link plate. If the upper shock mount moves up and down as you go between the holes you are indeed changing geo.

Here's why I say the other hole gives a move progressive shock rate: Visualize a triangle made by the link pivot on the seat tube and the two shock eyelets. When you move the lower mount back it make the angle at the upper mount more acute. This means less leverage at the beginning of stoke and a greater change in leverage through the stroke = more progressive. My friend had the same frame and when we moved it back he said it had a better feel and resisted bottoming more.
As for the reduced air volume, I'm thinking of following your lead (I have a DHX Air on a Bullit) and adding oil to my chamber which would reduce volume in small steps. I'm not too sure about this though cuz you don't hear people with coils complaining that there spring is too linear.

Good luck, maybe I'll shoot you a line this summer when I come over to ride Lost Lakes Trail.

[dowst]

Netwelle, I've got my DHX air on the same frame (06 coilair) and have been thinking about doing this mod for about 6 months now. How does it ride? Does it still have that really mellow/dead feeling midstroke?

Does it still perform as well on the smaller bumps/chatter with the lower volume can?

[Netwelle]

I feel like it is working real well. The small bumps are a bit stiffer but it still rolls through feeling pretty soft.

As for the Dead mid stroke. Not as much but it is still there a bit. Overall the ride just feels a bit more rigid. The only major difference that I can feel is the last part of the stroke stiffens real quick. Fast decents on rocky and bumpy stuff still feels pretty plush. When you jump or drop though you notice the most difference in that the bike recovers faster and does not bottom out.

I will let you know more on Monday. I am going to Fruita today. I plan to ride today the way it is. Then on sunday I am going move the shock to the back hole and give it a shot to see the difference. I will let you know how it feels.

[dowst]

I feel like it is working real well. The small bumps are a bit stiffer but it still rolls through feeling pretty soft.

As for the Dead mid stroke. Not as much but it is still there a bit. Overall the ride just feels a bit more rigid. The only major difference that I can feel is the last part of the stroke stiffens real quick. Fast decents on rocky and bumpy stuff still feels pretty plush. When you jump or drop though you notice the most difference in that the bike recovers faster and does not bottom out.

I will let you know more on Monday. I am going to Fruita today. I plan to ride today the way it is. Then on sunday I am going move the shock to the back hole and give it a shot to see the difference. I will let you know how it feels.

Thanks for the review/update. I think I'll order up the sleeve and see if I like it, can't go wrong for only $40. Did you ever replace the little bottom out o-ring? I opened mine up just yesterday and noticed that mine was broken also.

Just to compare, how much sag do you run?

[allsk8sno]

the hole only changes the rate, no geometry change whatsoever, however the change in rate isn't that much when compared to your air volume. i used to have a stinky with the 2 mounts and always ran it in the back one. try it and see if you like it...it will help with bottoming slightly, maybe allowing you to run lower pressures

[Netwelle]

Dowst,

There was a small rubber circle that came in the rebuild kit. It is not intended to replace the bottom out O-Ring but it works. I was able to stretch it over the main chamber. It is tight, but I was being super careful not to rip it. Its seems to work.

I am running just over half an inch of sag.

After riding this weekend I am positive I made the right choice. Everything seem to be just a bit better. I adjusted the rebound down a bit more it rode like a dream. I guess what I noticed most was that when rolling down into steep tight gullies and going up the other side. It does not come close to bottoming out. It has enough pressure to to just roll through it. At slick rock I would roll down into those small dips and the shock would compress and bottom out. Now it powers through without problems.

Also I had a few bad lines today and jumped into some pretty flat landings and it felt fine. I did not bottom out.

So over all I would say this is great MOD that will help anyone having the same issues. I never did put the shock in the rear holes. It felt so good as is I just left it.

[dowst]

Dowst,

There was a small rubber circle that came in the rebuild kit. It is not intended to replace the bottom out O-Ring but it works. I was able to stretch it over the main chamber. It is tight, but I was being super careful not to rip it. Its seems to work.

I am running just over half an inch of sag.

After riding this weekend I am positive I made the right choice. Everything seem to be just a bit better. I adjusted the rebound down a bit more it rode like a dream. I guess what I noticed most was that when rolling down into steep tight gullies and going up the other side. It does not come close to bottoming out. It has enough pressure to to just roll through it. At slick rock I would roll down into those small dips and the shock would compress and bottom out. Now it powers through without problems.

Also I had a few bad lines today and jumped into some pretty flat landings and it felt fine. I did not bottom out.

So over all I would say this is great MOD that will help anyone having the same issues. I never did put the shock in the rear holes. It felt so good as is I just left it.

I've tried both the front and rear shock mounts and have gone with the front. There's not much of a difference, but the front seemed a bit better. Maybe it's all in my head, I don't know. The bike took the 15 foot drop at Highland yesterday just fine with the suspension set up especially soft (need that 35% sag out here on the East Coast), so I'm not sure if I'd want the suspension curve that much more progressive anyway.

When I get the smaller volume air can I'll let you know what I think of it. If I decide to rig up a bottomout bumper when I bleed the damper I'll let you know how that works out too.

Again, thanks for the review.

[jeff da grom]

does anyone have any updates for how the bike changed handling characteristics...??? I'm thinking about doing this to my bottlerocket, but am concerned because it is my DH/FR bike and i still need it to be somewhat smooth over the rocks.

[Lelandjt]

What we are talking about is makes the spring more progressive. It will feel the same from top out to sag point. Almost the same from sag to half travel. Then it will feel firmer than your current setup and get much firm in the last bit of travel. Of all DHX Air equiped bikes I think this mod is most appropriate for the Bottle Rocket. You don't have much travel to use and you need bottoming resistance for big jumps = you need a progressive spring rate.
As an experiment do this before buying a new air sleeve: Find out the volume of the DHX and RP3 sleeves. Whatever the difference is, add that amount of 5wt oil in your DHX sleeve. You've now got the lower air volume with some extra weight. If you love it buy the RP3 sleeve to save some weight. If not experiment with more or less oil.

[jeff da grom]

Instead of screwing around w/the oil mod, i just bought it. $40 bucks... why not. It is awesome for the BR. I no longer have to fear a flatter landing from a drop.

[Netwelle]

lets us know what you think when you get it installed. I have not seen any negative performance issues. With all the adjustsments available on the shock you can still get a very smooth ride out of the shock when you need it. I just feel like it performs much better in the critical situations doing drops and rolling in slow to steep short gullies.

[urbaindk]

Why does cranking in the bottom out knob not accomplish the same thing? I thought that was meant to make the spring rate more progressive towards the end of travel.

Click Videos, then DHX Air Explained:
http://www.foxracingshox.com/fox_tech_center/owners_manuals/07/eng/2007_om_eng.htm

Admittedly, I know little about rear suspension tuning. I just got a Bottlerocket with a DHX Air, and I'm trying to learn. I have the sag set for my weight, etc. I played with the boost valve and bottom out a bit because it was bottoming out pretty easy. I'm riding mostly small stuff, 3-4' drops, etc. and it no longer has a problem handling that. I have no idea though, maybe the previous owner added some oil to reduce the volume already?

[teamcurtis]

I would love to hear the reports on this. I have switched to a vanilla on my enduro because of the marshmellowey mid stroke of the DHX air. If this mod really works it would be nice to drop the weight of the coil....

[mandown]

as stated above, the back hole doesn't change the geo, only the suspension characteristics. it is affectionately called "the huck hole" because it has a more progressive ramp up rate on big hits.

[Netwelle]

I would love to hear the reports on this. I have switched to a vanilla on my enduro because of the marshmellowey mid stroke of the DHX air. If this mod really works it would be nice to drop the weight of the coil....

It is very cheap experiment. You should just get the parts and try it for yourself. I am super happy with the results. If this did not work I was going to switch to a dhx 5.0 coil. As it stands now I am going to ride at least untill the resorts open up with the Air.

When keystone opens up I am going to play around with the Air and decide if it is going to work out. If not I think I will get a coil to swap out just for resort lift riding and save the air for pedaling trips. I keep everyone updated.

I say go for it. I love the change. I fell in love with my bike again on my last trip to fruita. The MOD works.

[Lelandjt]

Does anyone know the volumes of the two air cans? I'm thinking of adding oil to my DHX Air to reduce volume so knowing the difference will let me try to match the RP23 volume and then work toward the middle.