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  1. #1
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    2013 Fox 36 Float 160 Issue

    Hey All,

    Hoping you can provide some insight on an issue I am having with my brand new Fox 36 Float 160 FIT RC2 - it is topping out with only around 147mm of usable stanchion exposed. I've attached 3 photos of my situation:

    (1) - All the air let out of the fork to show where it bottoms out. I left the o-ring in this position in order to show the 'usable' travel in the next pics. You can see this is around ~6mm.

    (2)- This is with the fork pumped up to my typical riding pressure of ~54 psi. You can see there is about 147mm of usable and 153mm of total stanchion exposed.

    (3)- This is with the fork pumped way up to around ~95 psi (topped out) to show where full extension is. You can see there is around 164mm of usable and 170mm of total stanchion exposed.

    With 55 psi in the fork I can pull down on the lowers and feel somewhat stiff resistance against the fork topping out the last ~17mm of travel.

    Anybody seen this before? I called up Fox and they claimed that while I am riding I am achieving full travel even if it doesn't seem like it in a static position. I don't see how this is possible given how much negative force I have to apply to the lowers to pull the last 17mm of travel out of it. To their credit they did offer to take a look at the fork if I sent it in, I'm just hesitant to park my bike for a couple of weeks to do this.

    Thanks for any insight that you can provide.
    Attached Thumbnails Attached Thumbnails 2013 Fox 36 Float 160 Issue-stanchion-compressed.jpg  

    2013 Fox 36 Float 160 Issue-stanchion-typical-situation.jpg  

    2013 Fox 36 Float 160 Issue-stanchion-fully-exposed-1.jpg  


  2. #2
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    It's a fox (seriously), they're notorious for not having the full stanchion exposed, and not utilizing full travel. Just go ride it.

  3. #3
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    pic #2 looks pretty darn close to a 160mm fox to me. i have personally never seen one that is bang on 160, as arkon said, pretty common problem.

  4. #4
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    Yeah fox has integrity issues. My buddies who are on fox 160mm forks ride my lyrik and are blown away at how plush it is. "Wow your fork actually uses all of its travel this is kinda dangerous". No actually its normal to have a fork that uses all of its travel, you paid for that extra 10mm, you better get it! I've seen some fox forks only use 140ish mm of travel on 160mm forks. Fox might have all the snobs convinced but I think rockshox is years ahead.

  5. #5
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    Yeah I used to be a huge fan of Fox forks (I love their 32mm line when I road mostly XC, and some "all mountain"), but as soon as I started getting into their bigger forks, it was clear that Rockshox was eons ahead.

    I'd take my coil Lyrik over a Float or Van any day.

  6. #6
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    Also many people consider 160mm 6 inches of travel. It's actually 6.3 inches. The third picture is the only one close to that measurement and its nearly double his normal PSI which would make this bike a rigid bike. What's the point of having a fork with that much travel when it can only use it's full travel at a PSI that makes it impossible to access the full travel?

  7. #7
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    Do you have a Gibson SG?

  8. #8
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    If this is indeed an issue i think fox needs to address it. There is no need to advertise a product that it doesnt live up to. I have a fox 36 and i noticed that the fork doesnt use all of its travel all the time only with big hits. I know you can modify the fork to help this issues but i dont feel that i should have to do that.

  9. #9
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    I too have a Fox 36 Float that I feel has been pretty crap performance wise so far. This fork came on my NOS 2011 GT Sanction and it just is "blah". The seals are somewhat sticky and I am only getting about 4.5" of travel out of it, and that includes hitting some 4 foot jumps with it. Thinking of going rock shox instead......

  10. #10
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    i haev a Rock Shox Revelation (140) that is the same way. If I measure the same way you are (to the O-ring after releasing all pressure), i dont get close to 140. It is what it is and its not just Fox. If it rides well, does it really matter that much?

  11. #11
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    What I've understood is that the most usual problem with Fox air forks(especially 36's) is that they have too small air spring volume. This creates very progressive spring rate and often causes this kind of symptoms(mostly for small riders who need lower pressures) that if you set air pressure to get decent sag, it is impossible to get full travel, and if you set low enough pressures to get full travel(bottom out) the air spring is too weak to pull against the negative spring and fork does not get fully extent...

    This problem can be solved by shortening the air piston rod, which effectively increases the air spring volume and makes spring rate more linear. By doing this you are able to use higher pressures which will overcome the force of negative spring while more linear spring rate allows fork to fully extend while you are still getting full travel.

    I have a 160mm Fox Float R on my Covert, before the modification I ran with pressures between 15 and 20 psi!(sag about 30% and got almost full travel) After I shortened the air piston rod about 20mm, I can use pressures of about 45...50psi with getting 20% sag and using the full travel...

    Modification is fairly easy and instructions easy to find. Just disassemble fork so that you get the air piston rod out, remove pin&piston, shorten the rod by ~20mm, piston back, drill new hole, insert pin back, and re-assemble the fork. However, I understand that this can be a bit of a question mark whether or not to do this for a brand new fork, since this understandably voids the warranty...
    Last edited by Verttii; 07-12-2012 at 04:11 PM.

  12. #12
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    Quote Originally Posted by Verttii View Post
    What I've understood is that the most usual problem with Fox air forks(especially 36's) is that they have too small air spring volume. This creates very progressive spring rate and often causes this kind of symptoms(mostly for small riders who need lower pressures) that if you set air pressure to get decent sag, it is impossible to get full travel, and if you set low enough pressures to get full travel(bottom out) the air spring is too weak to pull against the negative spring and fork does not get fully extent...

    This problem can be solved by shortening the air piston rod, which effectively increases the air spring volume and makes spring rate more linear. By doing this you are able to use higher pressures which will overcome the force of negative spring while more linear spring rate allows fork to fully extend while you are still getting full travel.

    I have a 160mm Fox Float R on my Covert, before the modification I ran with pressures between 15 and 20 psi!(sag about 30% and got almost full travel) After I shortened the air piston rod about 20mm, I can use pressures of about 45...50psi with getting 20% sag and using the full travel...

    The interesting thing about this fork is that it is actually the most linear feeling Fox fork I have ever ridden. I'm not sure if they finally got it figured out but I actually don't think that it is too progressive and have been able to get it to bottom with the pressure correct for my sag/feeling and the HSC set very low.

    I also like the RC2 damper. The adjustments make a noticeable difference. The HSC adjustment with the linear feeling air spring have allowed me to have reasonable sag but not bottom out.

    Small bump compliance and stiction totally suck still. I am hoping that after a bit of riding it will smooth out.

    Now if I could just get it to actually have 160mm of travel, I would be happy with it. I understand the people who say 'just ride it' but when I paid $1000 for a fork I sort of expect it to have the advertised travel.

  13. #13
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    You are not going to notice that last 10mm of positive travel at your pressure. Besides, Fox says 160mm. They don't say all positive travel. Negative travel is still travel, and it is very important for traction. Just ride the fork.

  14. #14
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    To all the Fox skeptics, one more reason to get an Xfusion. I had a Lyrik for awhile and it was plush, but it definitely felt a little noodley! The Vengeance is ridiculously stiff and damn plush too.

  15. #15
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    Quote Originally Posted by Verttii View Post
    What I've understood is that the most usual problem with Fox air forks(especially 36's) is that they have too small air spring volume. This creates very progressive spring rate and often causes this kind of symptoms(mostly for small riders who need lower pressures) that if you set air pressure to get decent sag, it is impossible to get full travel, and if you set low enough pressures to get full travel(bottom out) the air spring is too weak to pull against the negative spring and fork does not get fully extent.
    This trade off issue should be solved with the RC2 cartridge as you can set the proper sag, have good small bump sensitivity and still have good support for big fast hits. I have a 2013 170 RC2 and I am using ALL of my travel. I am actually very impressed with this fork (coming from a TALAS 32 140). Sorry to hear the OP is having problems.

    Sent from my SGH-I897 using Tapatalk 2

  16. #16
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    Sounds like the negative spring is too strong. Not sure what the fix is, but it should be a full travel when not loaded. Sounds like a BS story from Fox to me. Wouldn't be the first time.

  17. #17
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    When you pumped it up to 54 psi, did you bounce/push on the fork a few times? This should be done when measuring sag and I would imagine the same principal applies here.

  18. #18
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    This is not a Fox-only problem, my Rock Shox does the same, my F32 100mm did the same until i played with the oil levels and my 32mm Float doesn't use the last few mm's either but it has 6mm extra of exposed stanchion.

    My Fox is actually much plusher than my Revelation but the Rev is stiffer and has more adjustments ( which i don't use anyway ).

    There will always be advantages and disadvantages to each, just ride the thing.

  19. #19
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    When Rockshox came out w/ travel gradient's on their forks there were a few folks reported their forks didn't measure the proper travel. Usually the threads would end like "just ride the fork, you won't even notice the difference". I had plenty of Marzocchi forks that would not measure the listed travel. The negative coil springs had more spring rate then the main spring. A simple test for the negative spring was to pin the front wheel down then pull up on the bars. OP send it to Fox or just ride it.

  20. #20
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    Quote Originally Posted by Adaptive View Post
    This trade off issue should be solved with the RC2 cartridge as you can set the proper sag, have good small bump sensitivity and still have good support for big fast hits. I have a 2013 170 RC2 and I am using ALL of my travel. I am actually very impressed with this fork (coming from a TALAS 32 140). Sorry to hear the OP is having problems.

    Sent from my SGH-I897 using Tapatalk 2
    This problem most likely does not have anything to do with the damping side, whether it is with basic open bath R or RC2 cartridge or anything. Problem is on the air spring side, and most likely related to negative spring. Negative spring is too strong or adjusted incorrectly, and it resists positive (air)spring too much with reasonably low pressures... When increasing pressure on air spring, its force will increase and overcome the negative spring.

    To demonstrate this on your own fork, just let all air out from the air side, at some point the negative spring starts pulling the fork in some, but not all the way to bottom. I don't remember now how long the negative spring was on my 36, maybe ~50mm or so...

  21. #21
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    I have the 12 talas rlc so I know the fork, if you need that extra travel you are fuc#ed. If it's really a problem sell it and get something different. I worked in a shop while I put myself through college and I've seen people worry about things like that. Gear whores looking to blame the bike, you will never notice it and it will not hold you back (my boss raced dh and wasn't that good had a 10k bike and always found something to blame, a guy put in a faster time on a hardtail). Personally I rarely use above 130 on my fork, if your hitting something that big your low speed compression will suck it up, if you do in just normal riding you don't have enough air in it.

  22. #22
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    I have the same problem on my talas 32 150. Some of it the negative sag issue, lift the bike off the ground and you'll see another 2-3 mm stancion, but I was still ~7mm short. Fox stretches the truth a tad, It's like horsepower ratings in cars, good luck ever reaching the car's advertised 0-60 time. But they are still great forks, I don't sweat it.

  23. #23
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    I was just about to grab one of these forks, thanks for posting this & letting us know.

  24. #24
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    Quote Originally Posted by Brian_Pal View Post
    The interesting thing about this fork is that it is actually the most linear feeling Fox fork I have ever ridden. I'm not sure if they finally got it figured out but I actually don't think that it is too progressive and have been able to get it to bottom with the pressure correct for my sag/feeling and the HSC set very low.

    I also like the RC2 damper. The adjustments make a noticeable difference. The HSC adjustment with the linear feeling air spring have allowed me to have reasonable sag but not bottom out.

    Small bump compliance and stiction totally suck still. I am hoping that after a bit of riding it will smooth out.

    Now if I could just get it to actually have 160mm of travel, I would be happy with it. I understand the people who say 'just ride it' but when I paid $1000 for a fork I sort of expect it to have the advertised travel.
    I know this modification works. I cut about 1 cm from the air piston shaft on my 32 float 150 RL. I weigh in at 155. I went from running 45-48 psi and getting 130 mm travel on the harshest rides. Now i run 70 psi and get full travel on most all rides. Cutting the air piston shaft creates a more linear spring rate. Thus you can run a higher PSI, the fork rebounds and uses the negative spring rate much better, and you still get full travel on big hits. This is something to consider. . .

  25. #25
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    It's the Negative Spring Rate. FOX only has one spring they put in so it's designed to work through out the whole PSI range of all riders. The 2011 FLOAT I had, it's negative spring was too soft so I would top out/clink when I pulled up and the fork sat at 170mm with only 50PSI.

    I'm going to say that FOX improved their design by installing a stronger negative spring. This also helps with initial travel/small bump.

    Can you tell me at what PSI does the fork sit at 160?

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