Why not just make a single crown gravity fork using existing 40mm stanchions? Since they had the tubes around, there’s a good chance Fox engineers tried this while developing this latest model. After tons of testing and rumors, they released this new 38 fork in April 2020. It’s now available on a number of bikes with 160-180mm travel, and we wanted to see why some riders might want to try them out. more rigid candlesticks.
The 36 and 38 have for the most part the same chassis specs and functionality, from rotary valves which release air pressure in the lows after a drastic gain in elevation, to the floating axle which allows the stanchions to telescope with each other. less friction and oil bypass channels designed to move a little more lubricant near the seals. These forks are well thought out from the axle to the crown.
In addition to the wider stanchions on the 38, the fork’s internal steerer tube is ovalized with additional material in the front and rear for added stiffness. Based on their measurements, Fox says the 38 fork is “31% stiffer in transverse shear, 17% stiffer front / rear and 38% stiffer in torsion than the 36”. All of that material makes the fork a bit heavier, tipping the scales about 300g deeper than the 36 we tested last season.
Is that extra weight worth it?
It is undeniable that this fork is more precise on the track. When you try to cut a few milliseconds into a few turns on a rough sliver of dirt, the 38 will follow your favorite line a little better than the 36, allowing you to ride a bit faster and shave time. Weighing 69kg as a full kit, the difference in stiffness between the two forks is probably less noticeable to me than someone who weighs more or rides harder and faster. Fortunately, there are loads of runners with more skill and courage than me, and for those people, the 38 could be a game-changer.
For example, Jesse Melamed and I are about the same human height, but he rides about 3 times faster than me and has more muscles in his upper body. Melamed chose 38 over 36 for his feel and strength this season, and it hasn’t hurt him. For athletes who aim for the finish line with hopes of a podium, the weight penalty is probably worth it.
Let’s not convert that finer fork into a DIY shade just yet. People who weigh a little less, like Laura Charles d’Orbea, are still very successful in the 36 forks race. In fact, there are a large number of athletes in the elite women’s and men’s fields who race on the Fox 36 or the RockShox Lyric equivalent. Party bikes are heavy these days regardless of the material of the wheels and frame, which is great because we can break fewer frames and fill fewer punctures. However, if there is a way to reduce the weight of these frames a bit that doesn’t significantly affect performance, why not drop a few grams? For many lighter riders and for those who ride with less head pressure, the 36 is still a good option.
In addition, we have to reach the top of these descents. If you’re not looking for the lunch-tour QOM or gravity racing, chances are the fork 36, Lyric, Helm or similar is very stiff. These newly lighter forks will burn less cookies on the way up, leaving a little more fuel for the fun part. If you enjoy all-day adventures on your gravity bike, these cookies will add up along the way.
The difference between the 36 and the 38 is not only the stiffness and the weight. The setup process also varies and I found the 38 to be a bit more difficult to compose. I started with the Fox recommended setup all around including air pressure, volume spacers, compression, and rebound clicks. I pumped the maximum recommended pressure for my weight class. It wasn’t great. As with most of the original setup guides, the first half of the trip was way too smooth, lacking both support and feedback. I tried adding high and low speed compression and speeding up the rebound a few clicks at a time, and as usual the best response was in the air spring.
If you reach this point, it may help to forget about the static sag measurement and configure your suspension to feel the way you want it first. You can make small adjustments later to find the balance between the ride feel and the distance remaining over the fun ring at the end of the descents. After all, it doesn’t matter whether you use the full stroke or not if you blow in the first half without adequate support. The next time you’re competing in an elite gravity race, watch the fun ring on the forks of pro racers as they gasp and whistle past the finish line. This ring will very rarely rest against the fork crown.
To dial in the 38in, I added air pressure a few PSI at a time, adjusting the rebound and compression along the way. As the fork got closer to a happy feeling of support, I noticed that I was only using about 130 of the 170mm on really rough trails. The next step was to remove one of the volume spacers and readjust the air pressure to find similar support with less progress. The place I arrived at is over 15 PSI above the recommended maximum pressure for my weight bracket, with a good amount of compression at high speed and a few clicks at low speed. Like the 36, the rebound knobs were fairly straightforward to adjust, and I regularly adjust them with a click or two depending on the terrain. Unlike the 36, “quick and easy” are not adjectives that relate to my experience with the 38 setup, but once all the strings are tuned it plays beautifully.
With the right setting, the 38 offers abundant support on successive impacts, and there’s a setting wide enough for a wide variety of riding styles and preferences. The fork’s smooth initial stroke maintains grip as well as the 36, despite the stiffer chassis, and the extra stiffness allows the rider to lean forward on front tire traction as much as their arm strength. permits.
One of my favorite things about mountain biking is that there is always something to learn and improve, no matter how fast or how inclined to ride. For this reason alone, I find the new Fox 38 an interesting upgrade. It allows for sharper steering and faster lines through the messiest rock piles, and I’m still intrigued by the speed. Whatever your relationship to running, if speed = pleasure this fork may be worth squashing. I can’t wait to see what other companies develop in this space. Fingers crossed that things get lighter from here on out.
Find the Fox 38 fork at Backcountry and other online retailers.
- More precise steering
- More rigid everywhere
- The harder the better
Advantages and disadvantages of the Fox 38 MTB fork.
- Longer installation period
- Limited benefit for light cyclists