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Discussion Starter · #1 ·
You are supposed to use 5 ml of float fluid in the air side of my fork (2012 Float 32 RL 80mm). I note I just can't get the last 5 mm of travel. I had the issue where the the Fox oil was leaking past the seal and into the air chamber..this reduced my travel and changed the spring rate until I dumped it; I have since replaced the seal so hopefully the oil migration issue is done. Can I just use 1/2 the amount of Float fluid to give me a little more air volume to help with that last 5mm of travel? Isn't it just to lube the piston?

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Your lack of full travel is considered 'within tolerance' for that fork. I don't think you are hurting anything to give it a try but don't trust to hope. I bet you won't see that last 5mm but let us know if you do! I've never tried that.

As an aside, I opened up a customer's fork yesterday and his Float chamber was COMPLETELY full of fluid. I've seen 20ccs in there before but never full! Amazed he's been riding it for months like that...

mk
 

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I like turtles
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Discussion Starter · #3 ·
I will try in a few days when the rain stops and see. If the air chamber has a bunch of oil in it, you need to replace the foam ring on the piston with the rubber one from Fox..at least that is what they told me would fix it..we will see!
 

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Yeah, I've fixed a bunch of them. I've just never seen one full before.

mk
 

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I like turtles
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Discussion Starter · #5 ·
Mine was really bad at one point with nearly zero fluid in the lower...all 30ml went to the upper. My fork was so stiff I figured something was wrong so did the rebuild...was I ever surprised!
 

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Your lack of full travel is considered 'within tolerance' for that fork. I don't think you are hurting anything to give it a try but don't trust to hope. I bet you won't see that last 5mm but let us know if you do! I've never tried that.

As an aside, I opened up a customer's fork yesterday and his Float chamber was COMPLETELY full of fluid. I've seen 20ccs in there before but never full! Amazed he's been riding it for months like that...

mk



Soooo I guess he wanted a fully rigid ...... and I assume that it still worked after.... that's impressive.
 

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Your fork has bottom out bumpers that takes up that last 5mm of travel. In order to use it all you need to drop several feet to flat (and then you'll need to replace the bumpers). Let us know how it works out for you! ;)

Have FUN!

G MAN
 

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Yeah, I've fixed a bunch of them. I've just never seen one full before.

mk
I would guess he slammed way, way too much oil in the lowers. As you said, 20cc or so is common, because the most oil that should be in the lower spring side leg is 30cc in almost any Fox air fork (180mm+ forks are 40 or 50ml).

We can do some simple math based around a 100mm fork with an air chamber that is 28mm in diameter (I don't know what the air chamber diameter actually is, but that seems reasonable for a 32mm fork, and I picked 100mm of travel because it is the shortest common travel setting). This gives us an air chamber volume of 61cc, and that doesn't account for the extra space above the air piston after the fork bottoms out. I would guess that brings us somewhere around 80cc of space in there. Obviously this volume can increase around 50% if it's a 150mm fork.

My guess would be that he someone read the oil volume for an O/B damper leg and jammed 160ml in to the spring side.
 

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I would guess he slammed way, way too much oil in the lowers. As you said, 20cc or so is common, because the most oil that should be in the lower spring side leg is 30cc in almost any Fox air fork (180mm+ forks are 40 or 50ml).

We can do some simple math based around a 100mm fork with an air chamber that is 28mm in diameter (I don't know what the air chamber diameter actually is, but that seems reasonable for a 32mm fork, and I picked 100mm of travel because it is the shortest common travel setting). This gives us an air chamber volume of 61cc, and that doesn't account for the extra space above the air piston after the fork bottoms out. I would guess that brings us somewhere around 80cc of space in there. Obviously this volume can increase around 50% if it's a 150mm fork.

My guess would be that he someone read the oil volume for an O/B damper leg and jammed 160ml in to the spring side.
Either that or it received multiple lowers/bath oil + seal services, but no air spring service.
If the air spring service wasn't done on forks with the oil migration issue, all the leg oil from multiple services would end up in the air spring even if the appropriate oil volumes were used when servicing the lowers.
 

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Put just enough float fluid to cover positive air piston -- probably 2.5-3ml. I've always done this for myself and others on pre-'13 floats with good results. On the flip side, I run a bit more than 5ml on my '13 CTD float to give it a more progressive feel instead of blowing through the travel.
 

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The fork was previously rebuild by a reputable shop so I'm really surprised that there was that much fluid in there. I think the Fox tables for oil volumes can be confusing though. But still...

He said the fork felt 'MUCH BETTER!' after the rebuild. I did it while he waited and showed him the oil volumes. His foamy thing below the Float seal was also folded on the piston...

Sorry for the hijack. Report back if you get that additional travel please.

mk
 

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Discussion Starter · #12 ·
Ok...did a race yesterday on a challenging trail that should have given me full travel. It did. Measured exactly 80mm to my ring. Only using a tiny bit of Float fluid in the air piston chamber seemed to work.

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Glad it worked out for you. That has been my experience with several Floats. Everybody has always been much happier with the performance after that simple change.

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