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First Look: The 2013 Fox CTD System

Just prior to Sea Otter, Fox invited us to check out their new facility in Scotts Valley, California. The new place is home to the engineers, designers, artists, marketing guys, head honchos, race techs and more people that keep things ticking.

It's not just bike stuff at Fox. Between snowmobiles, ATVs, UTVs, dirt bikes, indy cars, baja trucks, and several custom projects, Fox is very well versed in the art of suspension and ride dynamics.

Before heading inside, Cam McCaul kicks the tires on this rad baja pre-runner. Check out the suspension up front. HUGE!

Inside, Mark Jordan (JORDAN!) gives us the run down on the day's events - we'll get a brief tour, learn about the new Fox CTD line, and then hit the trail to test things out. Not a bad day.

Test lab time. Both Cam and the machine play a big role in making sure Fox's products are up to snuff.

Cycle after cycle, test after test, Fox ensures everything will last before it's brought to market. This CTD lever was at 50,500 cycles and counting...

Look familiar? Using data from one of Justin Leov's runs down the Maribor World Cup course, this machine is able to duplicate some of the harshest real world conditions in a controlled and measurable environment.

Place your bets! The boys in the shop are all supercross fans, and many of them have had the joy of working with some of world's best supercross riders. Whether MTB, MX, or something else, it all crosses over.

Buddha keeps things tidy. #workflair

The hallways were lined with World Championship jerseys. Nice work Gee!

With the short tour wrapped up, it was time to learn all about the new Fox CTD system and then head to the hills. Mark Fitzsimmons dreamt it up one day while out on the trail...

<font color="#000000">CTD stands for Climb, Trail, Descend. It replaces the previous high speed, low speed, and propedal adjustments on all 32 forks, 34 forks, and Float rear shocks. By doing so, Fox aims to make it easier for the front and rear suspension to be tuned on the fly as a balanced system.</font>

<font color="#000000">The new Fox D.O.S.S. post completes the CTD system. It's shown here in the fixed Climb (up), Trail (40mm drop), and Descend (down) positions.</font>

<b>Now that you're familiar with the CTD system at a high level, let's dive into each component specifically. We'll start at the front of our Yeti-SB66 test rig and work our way backwards. </b>

<b>First up, the new 26-inch Fox Float 34 fork. Fox previously only offered 34mm stanchion options in 29-inch versions, but for 2013 it will be available in 26-inch and 650b as well. Both new models feature the CTD adjuster and 160mm of travel. Also new for 2013 are 26 and 650b Talas 34 models.</b>

When the CTD adjuster is used, what's going on internally? In Climb mode, the Trail and Descend oil ports are blocked, forcing oil into the tiny Climb port and limiting suspension movement. A blow-off valve allows it to use some travel on hard hits. The blow-off is softer on trail forks than XC forks. In Trail mode, oil enters the mid-high speed compression shim stack. In Descend mode, oil enters the low, mid, and high speed ports.

In Trail mode, the CTD adjuster has soft, medium, and firm options. This is basically a low speed compression adjustment.

<font color="#000000">2013 also brings a new air spring curve. Fox has modified the air spring to more closely resemble a coil spring. It is now more linear with a slight bit of progressiveness at the end of the stroke.</font>

By optimizing the dropouts, brace trusses, brake mounts, wall thicknesses, and more, Fox was able to reduce the weight of their lowers by a substantial amount. Strength hasn't been compromised, though. The 34 is 0.44 pounds lighter than a 36, yet has the same ultimate strength.

The day's testing grounds were perfect for a trail bike. Bumpy much?

Descend mode engaged! This brand new fork was perfectly supple in Descend, but a bit too soft and divey at the recommended pressure over bumpier terrain.

<b>Even after pumping the fork up a few psi, we preferred the Trail "Soft" setting on descents. It helped prevent dive by adding some much needed damping. If you currently run your fork with a bit of compression damping, you'll likely be of the same opinion.</b>

Now for the rear shock. The Float CTD line is available in a variety of models. The CTD BV shown here uses boost valve technology which improves beginning and end stroke control. There is also a version with a bar-mounted remote lever, which can control the fork at the same time.

In Climb mode, oil can only flow past the small boost valve. This provides limited shock movement. ProPedal isn't gone, it's just integrated internally with CTD. In Trail mode, once oil pressure overcomes the ProPedal spring preload, the oil is allowed to flow freely. In Descend mode, oil bypasses the ProPedal spring through a gap.

Similar to the fork, you get soft, medium, and firm Trail mode options, indicated by 1, 2, and 3 on the adjuster. This is only available on the Float CTD BV shock without a remote.

CTD is tuned for each application - firmer for XC, softer for trail use. This is specified at the OE level and isn't externally adjustable.

As Fitzy explains, the new Float LV eyelet and air sleeve add flexibility and simplicity. No more swapping out air cans.

Another marked improvement for 2013 is IGUS shock hardware. It offers 10X the life and 50% less friction than the previous option.

After pedaling up the first lap to get a feel for Climb mode, we had the luxury of shuttles. This gave us more time to experiment with settings, most of which was used to dial in the fork.

<b>The rear shock performed very well in all modes. No changes were needed after the initial set up. Climb mode provides a nice solid platform for really getting after it uphill, Trail allowed quick adjustments, and Descend felt just like last year's offerings with the ProPedal turned off.</b>

<b>And now for the Fox D.O.S.S. post (if you were wondering, that stands for Drop On Steep Shit). We first saw this mechanically actuated post at Interbike two years ago. Since then it's been refined and is ready for launch. It comes in 4 or 5-inch, and 30.9 or 31.6mm options.</b>

As previously mentioned, it is limited to 3 positions - Climb, Trail (40mm drop), and Descend.

<b>Why only a 40mm drop and not infinite adjustability? Andrew Laird weighs in on the decision.</b>

<font color="#000000">Internally, the CTD positions are locked into place by a cam that forces ball bearings into three different grooves. When the lever is actuated, the cam retracts which allows the post to slide up and down.</font>

The D.O.S.S. lever can be mounted top or bottom, left or right.

The silver lever adjusts between all CTD positions, and the black lever adjusts between only Climb and Trail.

It also has three reach position options to personalize fit.

In our opinion, the lever is the D.O.S.S. post's weakest link. It's very bulky and we found it hard to actuate despite multiple reach options. Due to the post's design, the lever can be very difficult to engage when seated, requiring a slight butt lift before dropping the saddle.

The post is air sprung and can be adjusted to suit your preferences. Because there is no rebound damping, we found pressures near the low end of the adjustment range suited us best. Note that the return rate is reasonable throughout the full range.

<b>The post operation is very smooth. When the lever is pressed it slides freely with almost no noticeable drag.</b>

Up top there's a standard two bolt, zero offset clamp. It gets the job done nicely.

The upper post is forged then machined. This single piece design improves stiffness and durability greatly over standard multi piece designs.

<font color="#000000">A self-adjusting keyway mechanism prevents unwanted rotation.</font>

When lifted by the saddle, the post doesn't budge.

To our knowledge, the D.O.S.S. post is the first to rely on ball bearings. Note that several are missing from this cutaway.

We were curious if the bearings might be affected by the seat clamp. Andrew says they designed it prevent that from happening.

There's a fail-safe mechanism built in, so if you snap a cable mid ride you can still use the post manually. Good thinking guys.

<b>Lars Sternberg and Mark Weir put the CTD system to good use all day as they battled it out to see who could post the fastest lap on Strava. Weir won, probably because he always has his game face on.</b>

After several laps and suspension tweaks, we left pretty satisfied with what Fox has to offer for 2013. At the end of the day it's a quicker, easier way to reach presets, which is great for trail rides. Check back after a few months for our long term impressions of the CTD system. In the meantime, cruise over to <a href="http://www.ridefox.com" target="_blank"><font color="#FFFF00"><b>www.ridefox.com</b></font></a> for more about the new line.

With the switch to the CTD (Climb, Trail, Descend) system, Fox is completely revamping their line of XC and Trail offerings for 2013. They're also encouraging a change in the way we think about suspension, or ride dynamics if you will. To perform the best a bike needs to be balanced, which is exactly what they set out to do with CTD. Here's a first look at their 2013 line of forks, shocks, and the long awaited D.O.S.S. seatpost. - Photos by Brandon Turman and Colin Meagher

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