DW 5 Spot RP23 mod

[kiwirider]

The mod can be done to your shock, and if you are finding that it blows thru its travel, then the mod will help.

Give it a go - it's free and easy to undo if you don't like it.

[Vodzilla]

newbie question: is this mod applicable for air forks?

[wheatgerm]

newbie question: is this mod applicable for air forks?

Sorta. If you want to decrease the air volume in the fork (like this shock mod), add additional float fluid on top of the air piston. Remove the top cap and add a bit more. There should be 5 cc in there. Add some more if you'd like.

Are you having excessive bottoming issues with your fork?

[Vodzilla]

Sorta. If you want to decrease the air volume in the fork (like this shock mod), add additional float fluid on top of the air piston. Remove the top cap and add a bit more. There should be 5 cc in there. Add some more if you'd like.

Are you having excessive bottoming issues with your fork?

no issues yet. i'm just interested with what has been said in this thread about making the suspension more progressive.

[wreckingrob]

I used an old shampoo bottle. It's not quite 1.2mm thick so I cut it a little wider for the initial trial run - 25mm. It was a fairly large diameter bottle so it uncoiled nicely in the cylinder. Super easy to install. Didn't even need to take the shock off. I have a Yeti SB-66 and while the anti pedal bob from the Switch link is shockingly robust(yes, pun intended), bottom out on some drops or moderate jumps was an issue. Mid stroke, not so much. haven't ridden yet, but will post results.

[wreckingrob]

I used an old shampoo bottle. It's not quite 1.2mm thick so I cut it a little wider for the initial trial run - 25mm. It was a fairly large diameter bottle so it uncoiled nicely in the cylinder. Super easy to install. Didn't even need to take the shock off. I have a Yeti SB-66 and while the anti pedal bob from the Switch link is shockingly robust(yes, pun intended), bottom out on some drops or moderate jumps was an issue. Mid stroke, not so much. haven't ridden yet, but will post results.

Good results from this. Where I ride, there is a fairly large ramp(3' tall) to a down hill lander. It's probably a 6' or more drop so the the landing can be harsh. In the past, I would bottom out so hard it would blow the little sag ring off the plunger. Not anymore. Still have about a 1/4" left now. Awesome mode, and super easy.

[DGC]

Sorta. If you want to decrease the air volume in the fork (like this shock mod), add additional float fluid on top of the air piston. Remove the top cap and add a bit more. There should be 5 cc in there. Add some more if you'd like.

Are you having excessive bottoming issues with your fork?

2013 Fox Float CTD 140 is a good example of this. The air spring was redone. There is more air volume apparently and you will see in the coming months in many cases too much. The stroke is linear to the end. 10-15+ cc's ontop of the Fox air piston helps this out, the added fluid on the air piston does much like my shim does for the rear shocks. Same can be done in many air forks. If a said fork ramps up too quickly, it is worth a look under the air cap too see If too much fluid is there.

[Mr.P]

10-15+ cc's ontop of the Fox air piston helps this out, the added fluid on the air piston does much like my shim does for the rear shocks. Same can be done in many air forks. If a said fork ramps up too quickly, it is worth a look under the air cap too see If too much fluid is there.

Not a good idea to add oil into the positive air chamber of any fork or shock that has a self regulating air negative chamber to control volume.

When the air chambers open to each other on top out & self regulate, it creates the opening for oil to migrate down into the negative chamber. Then you will have a much lower volume neg chamber and the spring won't work as well.

It's ok to add oil to a positive air chamber for volume adjustment when the negative spring is coil or air added from a separate port (like dual air). The key being the pos air chamber is fully sealed & independent of the neg spring.

Edit: looks all the Foax Float forks have a coil negative spring:
2013 Float 130 - 180 Travel Adjust
I got the erroneous air negative spring from a Bike Radar review
Fox 34 Float 160 FIT CTD Fork Review - BikeRadar

Just a heads up.

P

[DGC]

Not a good idea to add oil into the positive air chamber of any fork or shock that has a self regulating air negative chamber to control volume.

When the air chambers open to each other on top out & self regulate, it creates the opening for oil to migrate down into the negative chamber. Then you will have a much lower volume neg chamber and the spring won't work as well.

It's ok to add oil to a positive air chamber for volume adjustment when the negative spring is coil or air added from a separate port (like dual air). The key being the pos air chamber is fully sealed & independent of the neg spring.

I saw that Fox is moving to an air neg chamber for 2013.

Just a heads up.

P

I just talked to Fox, they say that all the 32mm forks use a coil spring for the negative, it does however happen to be longer than previous, and the air chamber is bigger, or feels bigger, as you can feel the first time you push on a 2013 fork and keep in mind the air pressure it has in it. Case in point is my wife's fork set at 75 psi. with a rider weight of 125 pounds, and sag is still at recommended.
As far as putting more float fluid on the air piston for tuning more progressiveness to the last part of the stroke, that is just fine and they are recommending doing this. Maybe the neg air chamber is in 36 forks? Maybe the new 34's? Dunno, but Fox was quite adamant about coil negative springs in all their 32's.

[Mr.P]

I just talked to Fox, they say that all the 32mm forks use a coil spring for the negative....As far as putting more float fluid on the air piston for tuning more progressiveness to the last part of the stroke, that is just fine and they are recommending doing this.

Thanks for clarifying that the 32s still have the coil negative spring.

Edit: looks like the 34 and 36 Floats have a coil negative spring:
2013 Float 130 - 180 Travel Adjust
I got the erroneous air negative spring from a Bike Radar review
Fox 34 Float 160 FIT CTD Fork Review - BikeRadar

P

[Mr.P]

Here is a visual reference to the negative spring & oil issue for those who might be wondering. This is only for springs that use a self regulating air negative chamber.

Imagine the oil on top of the piston.
- the oil can migrate down into the negative chamber at the equalization dimple, filling up the negative chamber, resulting in a harsher shock.


More detailed nerdiness:
Tech Tuesday - What a Negative Spring is and Why it Makes the Coil-Spring Nearly Obsolete - Pinkbike

P

[DGC]

Thanks for clarifying that the 32s still have the coil negative spring. I do know that the Fox 34 is using an air negative spring. But I am unsure about the 36.

P

I rode a 34 Float 29er fork on a Specialized 2013 bike at their dealer event in July. Absolutely hated the fork. I could not believe how harsh and non responsive the fork felt, no matter what air pressure i ran or damping setting. But get on the 32 Float I got for my wife, and you would swear you were riding a coil fork.
Dunno If the 34 felt so bad because of the auto neg air, or maybe it was a bad fork, I even had their main tech check it out, stumped him as well. It reminded me of an old school mag 20/21 without the top out clunk....!!!!

[serhij]

I rode a 34 Float 29er fork on a Specialized 2013 bike at their dealer event in July. Absolutely hated the fork. I could not believe how harsh and non responsive the fork felt, no matter what air pressure i ran or damping setting. But get on the 32 Float I got for my wife, and you would swear you were riding a coil fork.
Dunno If the 34 felt so bad because of the auto neg air, or maybe it was a bad fork, I even had their main tech check it out, stumped him as well. It reminded me of an old school mag 20/21 without the top out clunk....!!!!

Funny, I had exactly opposite feeling. F32 felt OK, but there was no way I could use las 20mm of travel. F34 feels even better and it has much more linear feel at the end of the stroke.

BTW, DGC have you seen this ?
Fox Float Air Volume Spacer Kit: Installed and Reviewed - Bike Rumor

Looks like Your idea

[Vespasianus]

Funny, I had exactly opposite feeling. F32 felt OK, but there was no way I could use las 20mm of travel. F34 feels even better and it has much more linear feel at the end of the stroke.

BTW, DGC have you seen this ?
Fox Float Air Volume Spacer Kit: Installed and Reviewed - Bike Rumor

Looks like Your idea

Actually, if you ride several 32 Floats they will all feel different.

[Mr.P]

2013 Fox Float CTD 140 is a good example of this. The air spring was redone. There is more air volume apparently and you will see in the coming months in many cases too much. The stroke is linear to the end. 10-15+ cc's ontop of the Fox air piston helps this out, the added fluid on the air piston does much like my shim does for the rear shocks. Same can be done in many air forks. If a said fork ramps up too quickly, it is worth a look under the air cap too see If too much fluid is there.

I just want to correct the information I posted, it looks like all the Float forks have a coil negative spring, so the oil in the air spring side will work.
2013 Float 130 - 180 Travel Adjust
I got the erroneous air negative spring from a Bike Radar review
Fox 34 Float 160 FIT CTD Fork Review - BikeRadar

P

[DGC]

Funny, I had exactly opposite feeling. F32 felt OK, but there was no way I could use las 20mm of travel. F34 feels even better and it has much more linear feel at the end of the stroke.

BTW, DGC have you seen this ?
Fox Float Air Volume Spacer Kit: Installed and Reviewed - Bike Rumor

Looks like Your idea

I saw that. Mine is free, and can be made to whatever size you feel you need........
Free and customizable, can't beat that with any sized stick....!!!!!

[hoolie]

DGC, thanks. Rode Annadel today after doing mod exactly as you say. LOTS of rocky chunder, and decent 2 foot jumps at the end of ride (Burma). Never lost rubber band off the btm. Sweeeeet! Back to SAG set per Turner instruction manual. Now to dial in that red knob I am always too lazy to deal with! Thanks again, and thanks to guy from PUSH for input.

[mr2peak]

I've got to say, the Fox volume shims are worth it. Very easy to install, and a very noticeable change. It leaves the outer shell/extra volume air can to do its thing (extra rebound damping on repeated hits; why else would that air passage hole be so small?) so you really do get great results. I tried the plastic sheet shim method and found it helpful, but inadiquate. I'm sticking with the Fox shims.

[wheatgerm]

You may have done something wrong if this custom shim mod did not work for you. As you can read thru this thread, it had worked for many. Shims can be customized as well. I have a bunch of different sized shims.

Did you make a shim that was large enough to make a difference? I have a 13 mm shim that makes a noticeable difference. Perhaps the Fox shim you used is larger than the entire volume of the extra sleeve? This would make this custom shim mod lacking but also gives you less volume than the old standard low volume sleeve.

[mr2peak]

The sleeve shim made a difference, but not enough for me. I'm a light rider, so I never had enough PSI in the shock to support me when taking big hits while maintaining sag. Also because of the low PSI I suffered from the rebound being too slow. The large shim has helped the bottom out problems as well as sped up the rebound.

However, I will continue to experiment with the DCG mod. It cleans up the mid-stroke wallow (extra rebound damping on repeat hits) much more effectively than the Fox shim kit.

In summary:
Fox shim kit inside the shock body helps with bottom-out issues
DCG mod shimming the sleeve for increased mid-stroke support

[dustyduke22]

Any word how this mod works with the new Boost Valve rp23's?

[Vespasianus]

Any word how this mod works with the new Boost Valve rp23's?

It won't. Fox did away with the sleeve design. Now instead of being able to modify the air volume with a 0.05 dollar piece of plastic, you need to buy a 25.00 dollar piece of plastic.

[vladol]

sorry double post...

[vladol]

it is actually still possible. Yesterday I did this mod on my Float CTD with high volume air canister, but haven't tried it on the trail yet...

[eddstinkyjr]

hi I have a 2005 fox float r shock (just been serviced) and it bottoms out way too easily, even if I have 10% sag. So I would really like to give this technique a go since people say it works great. Only problem is can I use some other kind of plastic instead of the ski base stuff ?
I do live in the alps actually but will a ski shop have this ?
Thanks, I will be grateful for any help !
Eddy

PS: great post ! really helpful !