First Look: Inside the 2014 FOX 40 FLOAT RC2 and DHX RC4 12

<b>Travel back in time with us to the 2012 Plattekill ProGRT, where Trek World Racing received their FOX 40 FLOAT RC2 forks, known at the time as the FOX 40 RAD or AIR 40.</b>

<b>Leov was pumped, too. Thousands of miles away in Leogang, the other top FOX athletes received their forks as well. Then the podiums came...</b>

<b>In early March 2013 we travelled to La Fenasosa Bike Park in Spain for the official unveiling of the new 2014 FOX 40 FLOAT RC2 and DHX RC4.</b>

<b>The 2014 40 FLOAT RC2 represents the first major chassis and spring change since the fork was born in 2004.</b>

<b>The final product is a result of countless hours of work with the help of the RAD (Racing Applications Development) Program, aimed to give the Pros the best tools possible to succeed.</b>

<b>Unknown to the public, the Pros were racing on new spring systems and all new chassis structures were being developed back at FOX.</b>

<b>Sik Mik Hannah lets it fly during a test session in Leogang just prior to the VDS World Cup.</b>

<b>Perhaps the biggest change is the switch from a coil spring to an air spring, which immediately dropped the weight by 152 grams.</b>

<b>A progressive coil system called PABLO eventually led to the air spring system shown here.</b>

<b>Between air pressure adjustments and a new volume adjust feature, the fork can be tuned in innumerable ways, from near linear (coil-like) to very progressive. The low pressures required (45-80psi) reduce seal tension and friction.</b>

<b>Situated in the lower portion of the fork, the unique negative spring assembly is the key to the air spring's supple ride qualities. The largest spring is titanium to help save additional weight.</b>

<b>During lab testing, only a 0.5 psi pressure change was observed during simulated runs. That's a change even Ratboy wouldn't notice (if his wheels were ever on the ground, that is).</b>

<b>No, they aren't grease zirks. New air pressure relief valves make it simple to reset the seals to a relaxed state. After a big elevation or temperature change, a few quick button presses makes the fork feel instantly better.</b>

<b>Because the FIT RC2 damper has to do less work, they were able to remove the bottom out circuit completely, saving 24 grams. Only high-speed, low-speed, and rebound remain, in addition to the air pressure and volume adjustments.</b>

<b>First seen on Gee's bike, the inverted FOX DH fork was an experiment that taught the FOX crew many lessons, and ultimately encouraged a chassis structure change.</b>

<b>With an already tried and proven air spring system in place, the FOX crew set out to remove weight from the chassis and gain a small amount of bending compliance, allowing the fork to track better.</b>

<b>Weight loss across the board was massive, including 45 grams from the upper crown.</b>

<b>Small tapers at the bottom of the stem mounts helped with the weight loss.</b>

<b>An additional 18 grams was pulled from the lower crown while reducing bending fatigue and improving downtube clearance.</b>

<b>As a result, the lower pinch bolts were moved to the front, matching the top crown.</b>

<b>New butted upper tubes are tapered from thick to thin, dropping an additional 89 grams.</b>

<b>The lowers saw massive changes as well, starting with the web truss, which benefitted from recent casting and molding advancements.</b>

<b>The lowers are also more form fitting near the brace, which helped reach their bending compliance goal.</b>

<b>8-inch brake post mounts are a welcome change to the fork. The total weight loss is an impressive 1.04-pounds, which brings the weight of the 40 down to just 5.98-pounds (2711 grams)!</b>

<b>Anyone who has stripped or broken an axle bolt will be pleased to see this clamping improvement.</b>

<b>Also new is a 650B (~27.5-inch) option. The lowers were kept as compact as possible to keep the overall height low.</b>

<b>Is 650B a game changer? Which teams and riders are using it? We'll have to wait and see...</b>

<b>Will we see improvements to the rest of the air sprung FOX fork range? That's a definite yes. Notice the RAD fork already being tested by Enduro World Cupper, Nico Lau.</b>

<b>Not only is FOX introducing a new fork, but there's a much improved DHX RC4 shock coming out as well.</b>

<b>The biggest change is the shift of some mid and high-speed damping from the reservoir to the main piston.</b>

<b>The change from a 5/8-inch shaft to 1/2-inch contributed much of the damping shift.</b>

<b>Ultimately there's less friction, making the shock more responsive and sensitive than ever before, resulting in more traction.</b>

<b>Canadian huck fest take one. Because progressiveness is being built into more and more DH bike linkages, there was less need for a progressive damping system.</b>

<b>Air assist and air assist volume adjusters help fine tune the spring rate and progression.</b>

<b>Minnaar's first run with the new air spring system was also his first on a FOX 40 and rear shock.</b>

<b>His reaction at the bottom of run one was one of complete surprise, and he said he "felt somewhat short handed" in years prior.</b>

<b>The be all, end all for any racer is whether or not race times improve. For Minnaar, he felt that was the case.</b>

<b>Ultimately, behind the scenes efforts add up to seconds saved on race day, and the new product is the culmination of FOX's hard work.</b>

<b>The 2014 40 FLOAT RC2 will be available this summer at a price tag of $1,700, and the DHX RC4 comes in at $600 and will drop this May. Check out <b><a href="" target="_blank"></a></b> for more details, and stay tuned for our ride impressions from Spain.</b>

The 2014 FOX 40 FLOAT RC2 and DHX RC4 have been years in the making. You've seen them on the Pros' bikes, in the pits, and at the races... Now they're available to everyone. We visited Spain's amazing La Fenasosa Bike Park to join the Santa Cruz Syndicate and FOX for the official launch of their best suspension systems yet. This slideshow offers an in-depth look at the technologies, innovations, and behind the scenes efforts that went into making them a reality.

For more details, visit

Photos by Thomas Dietze, Brandon Turman, and Matt DeLorme
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  • sino428

    3/28/2013 3:35 PM

    I read that the air spring kit can be retro fit to older model Fox 40's. Do you guys have any detail on that, like how much it will cost, what if any parts need to be changed, can it be done by the average person on their own etc?

  • Randy_Geniec

    3/27/2013 4:43 PM

    "Compliant"= flex...That is alot of plastic in there for $1,700.

  • bturman

    3/27/2013 5:13 PM

    Correct on the flex point. Sometimes a bit of flex is a good thing. FOX also said that the new fork components have the same same ultimate strength values as the 2012 fork, and the same or better fatigue results in lab tests due to crown and casting changes.

  • Brendon_Newton

    3/27/2013 8:11 AM

    Yeah Turman... Pretty much covered all the bases!

  • Uncle Cliffy

    3/26/2013 9:04 PM

    What? No 97% jokes...?

  • Krispy

    3/26/2013 4:34 PM

    Pretty much everything we've wanted. A more compliant, tunable, 40 with all the little imperfections FIXED! The 2013 air system on the 34 is much like what's coming in the 40, and i am a big fan.

  • sideshow

    3/26/2013 12:52 PM

    Doesn't get much more comprehensive than that. Well done Vital and Fox for breaking that down so concisely.

  • mrpowerjd

    3/26/2013 11:51 AM

    Want. One. Now. Plllleeeeaaassse?

  • gojammedia

    3/26/2013 11:35 AM

    Great set and interview!

  • bjenson

    3/26/2013 10:53 AM

    wow. a 40 lighter than a boxxer keronite. nice work fox!

  • FatNuts

    3/26/2013 9:58 AM

    Fox, brace yourselves for a swarm of warranty issues from old fox 40 owners machining out their crowns

  • rallysmurf

    3/29/2013 9:35 AM

    but have you ever seen a broken 40 arch?

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