FOX’s 2010 line of bicycle suspension brings DH technology to the cross-country scene.
- By Zack Vestal
- Published Apr. 18, 2009
- Updated Apr. 20, 2009 at 7:55 AM UTC
Editor’s Note VeloNews technical editor Zack Vestal attended FOX Racing Shox’ 2010 model year introduction this week. This is his second report on he new products. His first report was published Thursday.
FOX Racing Shox product and marketing managers had some difficulty at Zaca Station, peeling the cycling media away from the desert trucks and motorbikes on display. But when Mario Galasso, bike product manager, began showing off the new 2010 FOX forks and rear shocks, he quickly earned everyone’s attention.
FOX 2010 bicycle product
Rather than completely reinventing already-proven dampers, the biggest news is that FOX has adapted technologies already found in their downhill products to the needs of cross-country and trail riders. The result is a highly evolved, lighter weight line of front and rear suspension products with a long heritage in downhill and motor sports racing.
The two principal technologies that FOX is introducing are a redesigned FIT damper for the entire line of 32mm forks, and Boost Valve damping for the RP line of air sprung rear shocks. Both of these damper platforms are newly adapted for XC and trail use.
On the downhill side, all-new coil-sprung rear shocks DHX RC2 and RC2 with highly tunable damping are introduced, while the lighter weight DHX Air 5.0 gets a retuned Boost Valve.
The FIT damper, redesigned for 32mm forks
The FIT damper (which stands for “FOX Isolated Technology”) has been used in the 36mm and 40mm fork line for the last several years. For 2010, it’s redesigned for the smaller, shorter travel forks with 32mm stanchions.
(The FOX line of forks is divided into cross-country and trail forks with 32mm stanchions and up to 150mm travel, heavier-duty forks with stiffer 36mm stanchions and 160mm travel, and downhill forks with 40mm stanchions and 200mm travel).
The damper is a sealed cartridge rather than an open bath, which eliminates fluid aeration by keeping the damping oil enclosed and separate from air. Furthermore, it reduces oil volume, which helps reduce damper weight by a minimum of about 70 grams in any FIT equipped fork. It also lowers un-sprung weight for faster tire response. A unique bladder design at the top of the damper allows oil to cycle through it with a minimum of friction, but keeps the oil contained in the upper part of the cartridge. The ultimate result is that a top of the line F100 RLC fork now weighs under 3.2 lbs, and a 2010 F120 RLC loses 125 grams from its ’09 counterpart.
With the new 2010 FIT damper, rebound adjustment and lockout force adjustment have traded places from 2009: rebound adjustment moves from the top cap to a red knob at the bottom of the right fork leg, while lockout force adjustment takes the center dial on the top cap. All compression damping is now adjusted at the top of the fork. Another revision to the damper includes a modified, wider range of low-speed compression adjustability. Low speed compression adjustability is still dialed via a ring on the top cap.
The FIT damper for 32mm forks comes in RLC and RL versions: the RLC includes a lockout lever, lockout force adjustment, external low-speed compression damping adjustment, and rebound damping adjustment; the RL has a lockout lever and rebound damping adjustment, but lacks the external compression adjustability.
Other revisions to the 2010 fork line include:
- A wide range of available fork shapes and sizes. Almost every fork in the line is now available with a 1.125 to 1.5-inch tapered steerer, including the 29er forks.
- Lower leg options also proliferate, such that FOX’s 15mm QR system is available on almost every fork, again including 29er forks.
- Furthermore, for those forks equipped with remote lockouts, the levers are now available in both right and left hand versions.
- Finally, all the air-sprung forks have reworked spring curves for full travel at correct sag, and have less slider friction.
Boost valve brought to the RP23 and RP2 rear shocks.
Boost Valve is FOX’s patented position-sensitive damping, first developed in motocross and downhill applications. In the most basic sense, position-sensitive damping helps control compression of a shock depending on whether the shock is in the beginning, middle, or end of stroke. It’s the same principle that keeps a Ford Raptor desert truck hugging the terrain — softer damping at ride height gives improved stability, traction and comfort, with stiffer damping at the end of stroke for bigger hits without bottoming.
For 2010, Boost Valve makes its way into the lightweight XC, trail, and all-mountain RP air shock line. Boost Valve technology is also employed in the new flagship downhill shocks, the DHX RC4 and RC2, but on these dampers, it’s used only for bottom out control, with separate high and low speed compression adjusters handling the beginning- and mid-stroke.
Typically in an air shock, the progressive rate of air spring curves is used to control bottom out. In 2010 FOX RP shocks with Boost Valve, bottom out control is shifted to the damper, by increasing compression damping at the end of the stroke. The intended result is a plush, bottomless feel throughout the stroke, less ramp-up, and the ability to run correct sag settings and achieve full travel without bottom out.
At the beginning of shock stroke, Boost Valve aids the already-proven ProPedal platform settings. By shifting the damping load of high compression damping settings (firm ProPedal), Boost Valve helps the shock respond more quickly to sharp hits without over-compressing.
Adam Craig is already a fan. “Just having that RP23 now with the Boost Valve that you can run ProPedal in a lot more situations helps,” he said. Craig added, “Before, on a Trance X with the shock open, you are feeling that 5 inches of travel, but now you can run it in ProPedal more of the time, to keep it from wallowing on short, sharp climbs where you can make up a few seconds.”
Another big advantage of Boost Valve-equipped shocks is that they can easily be tuned by FOX technicians to suit different bike frames and different leverage ratios. Boost valve behavior depends on nitrogen gas pressure behind the internal floating piston (IFP) in the damper, and by adding or reducing IFP pressure (in the range of 200-300psi), FOX tuners can soften or firm up the ProPedal damping. At the original equipment level, this lets bike manufacturers precisely match shock performance to the frame design and overall desired feel. And in fact, product managers work very closely with FOX tuners to get precisely the damper feel they are looking for on the bikes they spec.
ProTune introduced at Sea Otter
Discussed briefly at Zaca Station, and formally announced at Sea Otter, FOX is starting a new program called ProTune. It is a custom tuning, aftermarket-oriented program that is aimed at helping FOX owners update their older product to more current technology levels. It can also be used by riders who feel that they fall outside the standard tuning parameters developed by FOX and the brand’s OE partners.
According to bike product manager Mario Galasso, the program will start by helping customers with the set up process, such that they can optimize the performance of their suspension without sending it in for tuning. For the few that have additional needs or fall outside the parameters used in OE tuning, they will have the opportunity to ship their fork or shock to the company for custom work. FOX will then use tuning history from the customer to change the tune to suit the customer, before returning it.
ProTuned products will be re-decaled to show they’ve been through the program.
2010 product on the trail
The best part of FOX’s media launch was the chance to ride 2009 and 2010 product back to back. Testers started the day on Yeti 575 demo bikes with 2009 forks and shocks, after being set up for sag and damping by FOX suspension tuners. After lunch and some discussion, we remounted the same bikes, which had been fitted with brand new, just unpacked 2010 suspension. The difference in ride performance was substantial.
Almost immediately I noted smoother, quieter performance from the TALAS FIT RLC fork. The 2009 open bath damper always made a little noise, but the 2010 FIT damper is silent. Small bump sensitivity seemed improved. Also, I picked up on the wider range of low-speed compression adjustability, such that I was able to set it just firm enough to tune out pedaling input and brake dive, and then forget it, regardless of riding the test track or the asphalt to get there.
In the rear shocks, I noticed less ProPedal platform — or rather, less obvious ProPedal platform. Pedaling motion was still mostly damped out of the ride, but without the firm sensation of a lockout-like platform. On the 2009 RP23, I rode primarily in ProPedal position 2, for a mildly firm pedal platform that would easily blow open on hits. With a 2010 shock, I found that the firmness was gone, even in ProPedal position 3. In fact, the difference between ProPedal 1, 2, and 3 was hard to discern. However, the upside included remarkable, almost coil-spring-like response to sharp hits, as well as better response to small bumps. Rear suspension performance was as buttery and supple as any I have experienced in an air shock.
Several of the testers commented on the loss of characteristically firm ProPedal position 3 “lockout.” In contrast to the fork lockout, which is comfortably solid for pedaling roads, the new RP shock never felt as firm as I’ve come to expect. Personally, I can envision situations in which I would like to feel a more solid platform.
However, several factors are likely at work. For one, the new Boost Valve is designed such that it is tuned according to manufacturer’s specification to suit the bike on which it is used. Product managers can request firmer or softer ProPedal behavior (via IFP pressure) based on the bike’s leverage ratio and intended performance. Furthermore, riding Yeti 575 bikes (which are leveraged to take advantage of mid-stroke performance) undoubtedly played a role in how the new shock felt. FOX engineer Joshua Yablon reminded me that the range of original equipment specification for IFP pressure (and the resulting ProPedal firmness) includes bikes that are meant to be soft and supple, as well as a few that are meant to have a firmer “locked out” sensation.
With 2010 mountain bike product again evolving, by borrowing from the success built across all platforms, FOX Racing Shox should have no difficulty leading the pack in the year to come. Look for more impressions from the trail as we get the chance to spend more time on the new products.
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FILED UNDER: Bikes and Tech
Zack Vestal
Zack joined VeloNews in 2009, bringing 15 years of industry experience to the Tech Editor position. Most recently manager and mechanic for the Trek-VW mountain bike team (2004-08), he has an unused geology degree from Whitman College (and a well-worn Ph.D. from the school of hard knocks). Vestal covers the latest in cycling gear online, and brings in-depth perspective to the magazine.