You don't need to be a code cracker to figure out the missing number in its sequence of forks, but up until now very little else was known about the Fox 38
The Fox Float 38 is the new addition to the range with 38mm upper tubes and 160-180mm travel. Designed for Enduro racing (and e-bikes).
Fox Float 38 need to know
- New addition to the Fox fork range with 38mm upper tubes
- Designed for Enduro racing and e-bikes
- Travel options are 160, 170 and 180mm
- Available in 27.5in and 29in versions, with 37, 44 and 51mm offsets
- Standard 110x15mm dropout spacing gets a floating axle design that improves alignment
- Lower leg channels increase ambient air volume and aid lubrication
- Bleed ports on the lowers, just like the 40
- Grip2 damper now gets VVC valving on the compression circuit
- No coil option – just the Float Evol air spring
- Available in Factory, Performance Elite, Performance and e-bike models
New products are often hidden in plain sight. Not Fox’s latest enduro fork. Developed under its RAD program and raced to victory by Richie Rude in the penultimate rounds of last year’s EWS, the arrival of the Fox Float 38 is one of mountain biking’s worst-kept secrets. For a prototype fork with so much exposure though, Fox did manage to keep tight-lipped about the details. Sure, you don’t need to be a code cracker to figure out the missing number in its sequence of forks, but up until now very little else was known about the Fox 38 and how its arrival would impact the rest of the range.
Let’s take a closer look at the new Fox Float 38 from the bottom up. And what better place to start than the front hub? The Fox 38 gets standard 110x15mm dropout spacing, but because front hubs aren’t created equally, Fox has employed a floating axle mount to allow for better alignment of the lower legs – which in turn reduces friction. A floating spacer in the drive-side dropout is adjusted to match the hub and it’s held in place with a pinch bold. And the real beauty of the design is that it is set-and-forget, so you still get all the advantages of the 15mm QR lever. The new floating axle will also feature on the latest 36 fork, and if you want to save weight and boost stiffness on the new 38 or 36, a dedicated Kobalt-X axle can be used to replace the floating sleeve and QR axle. Which makes it very similar to the floating axle system on the Öhlins RXF 36 fork.
Now let’s move on the lower leg design. On the back side of the 38 there’s are two distinct ribs running up the lower legs. At first glance these look a lot like reinforcements in the casting for improved stiffness and strength, but they actually indicate what’s going on inside the fork. The ridges are formed by air channels that run up the inside of the fork lowers, effectively increasing the ambient air volume in the lower legs. So, as the fork compresses and the residual pressure in the lower legs starts to build, the increased volume in the lowers created by the air channels helps reduce the associated ramp-up. A secondary benefit of the channels being that they allow the free flow of lower leg lubrication to the bushings and foam rings, which further reduces friction.
And because air bypassing the main seals can also build up unwanted pressure in the lower legs, Fox has added bleed valves on top of the channels, making it easy to purge any additional air.
The arch of the lower casting has also been revised to improve stiffness; that’s right, it’s not all about the headline grabbing 38mm upper tubes. It also juts out more to provide extra clearance at bottom out, something that’s necessary with the increased trend for oversized head tubes and shorter offset forks.
As we already know, the 38 has 38mm upper tubes, but what about the crown that’s attached to them? Fox has done something really clever here. To increase fore-aft stiffness and strength, the 38 gets an elliptical steerer tube. Externally, it looks just like any other 1.5in tapered steerer, but flip the fork upside down and you can instantly see that Fox has retained extra material where it’s needed most. It’s a feature that’s exclusive to the new 38, where the increase in strength at the steerer/crown junction is a really critical feature for longer travel single-crown forks designed for bikes with slack head angles. And by using three unique crowns, Fox offers the 38 fork with 37, 44 and 51mm fork offsets.
With all of the updates to the chassis, Fox is claiming that the 38 is 31% stiffer in transverse shear, 17% stiffer fore/aft and 38% stiffer torsionally than a 36. It doesn’t say if these figures are equated for travel, but it safe to assume that it’s going to be stiffer.
That pretty much covers all of the major development to the 38 chassis, so now we’ll take a closer look at the updates to the internals. The latest Grip2 damper retains its four-way adjustment, so you still have high and low-speed compression and rebound dials at your fingertips. The new compression circuit also gets Fox’s Variable Valve Control (VVC), which means the adjuster now adds stiffness to the high-speed compression circuit, rather than simply increasing preload. First introduced to the rebound side of the Grip2 damper cartridge, VVC should now offer a better range of usable adjustment on the compression side. Also both high-speed adjusters on the Grip2 damper now have eight clicks to match the X2 shocks.
And speaking of the X2 shocks, Fox has made some updates in this department too. The air-sprung Float X2 and coil sprung DHX2 both get chassis and damper redesigns that see the low-speed rebound adjuster switching to a needle design on the shaft end of the shock, while the climb switch is relocated to the reservoir and offers a firmer lock-out than before. There’s also a new ultra-low friction, highly durable damper shaft finish, and guess what? It’s not Kashima.
The new Fox 38 is available with 160-180mm travel for 27.5in and 29in wheel sizes. There are Factory, Performance Elite, Performance and e-bike models. And in addition to the stock orange and black colour ways, Fox has also release a limited run of brown, pistachio and grey 36, 38 and 40s as part of its heritage line.
UK Pricing to follow.