Prototype Fox AX Adventure Cross “gravel” suspension fork spotted

prototype fox adventure cross gravel road bike suspension fork spy shot
Photo pulled from Peter James Lucas’ Instagram account, provided by

Spotted on then quickly pulled from Shimano’s California-based tech rep Peter James Lucas’ Instagram account was this image of a prototype Fox AX Adventure Cross suspension fork mounted to what’s presumably his Santa Cruz Stigmata cyclocross bike.

Fortunately, our friends at grabbed the image before it was deleted and kindly shared with us, check out their prognostications here. Their guess is the same as ours, that it’ll be built on the lightweight, minimalist SC32 XC fork’s platform, but with travel dialed back. Considering how good the Lefty Oliver-equipped Cannondale Slate and any bike with the Lauf GRIT feels on rough roads, it’s not a huge surprise to see more options coming. We’re expecting some gravel-related news from sister brand Easton in April, so perhaps we’ll learn more then. Until then, keep those eyes peeled…


40 thoughts on “Prototype Fox AX Adventure Cross “gravel” suspension fork spotted

  1. ..i’m not sure why this is new, astonishing.

    i had white brothers build me a short travel fork waaaay back in the early 2000s and i used it on my steel Trek cyclocross bike for a few years before selling it.

    next year will be dropper seat posts, ha!…

  2. I’d think building frames and forks with 40mm or even 45mm tire clearance would offer enough suspension without making road bikes into MTBs.

    1. Yes, and if people who just accept that 700c wheels aren’t ideal for “gravel” applications, then we could have the suspension we need without the weight and added complexity of a friggin’ suspension fork.

      1. What is the ideal wheel size for gravel, then? Tire and wheel choice point to 700c. Sure, 650b could keep stays shorter and all that jazz, but at the expense of rollover.

      2. I would rather have clearance and a 700×50 tyre than 650×50. Same bump flattening but even faster rolling, the XXL frames I ride around on have more than enough space for it in terms of fork and stay length.

        1. The obvious exception is VERY tall riders, but that’s outside the norm. The majority of bikes in this category would benefit from 650b wheels. A 54cm frame with 700×50 tires is going to ride like garbage, especially compared to a bike with a comparably wide wheel and shorter stays.

          1. There are 29ers that can take a 2.4″ or even 3.0″ tire and have chainstays in the 710-725mm range, so I don’t see why 700×50 would be so difficult on a gravel bike. Especially with 1x.

        2. Bicycle Quarterly did tests on this and nope, not faster rolling. Bottom line is suppleness of the casing matters more than volume or diameter.

    2. FWIW – When importing a bike with 700c wheels into the US, the tire clearance has a huge impact on the tariff (duty rate). If it allows for tires with cross sectional diameter EXCEEDING 4.13 cm, there is an 11% duty rate, versus 5.5% for bikes that limit clearance to BELOW 4.13 cm . This factors greatly into the design of CX/Urban/Gravel bikes.

      1. what?? – OK I had to look this up. That is some of the craziest sh*t I have ever heard of. Why on earth is that actually a thing?

        1. That is a question for the WCO/WTO ! The entirety of the tariff covering bicycles (8712.00) and their parts/accessories (8714.99) are due for a restructure, but without pressure from the industry, it isnt likely to happen until customs realizes they are missing out on $$$ or inhibiting the US GDP.

          1. It was to protect the US bike industry back in a time when the US still manufactured bikes. Not sure where 650b falls in terms of tariffs but strongly suspect this is one reason why it’s become the new standard on MTBs.

            BTW if you want truly crazy look up the “chicken tax”. In a nutshell it’s a tax on light trucks, brandy and potato starch imposed in retaliation to Germany taxing imports of US chickens. No joke. This is why you don’t see VW pick-ups in the US even though they do make them.

            1. That is always CBP’s tag line; “protecting commerce within the US”. Often times that only tells part of the story, but you are definitely on the right track.

              The current tariff structure and rates were established 1989-1991 in the US, which is unfortunately near the time that MTBs started taking off and brands began to outsource manufacturing. Too little, too late to make a difference.

              650b bikes need to adhere to the same tire clearance and weight restrictions as 700c bikes hit the 5.5% duty rate.

              Here is a link to the specific subheading of the HTSUS for anyone interested in seeing how customs assigns duties for complete bikes:

  3. Like said above, low pressure, bigger tires can handle most of the small chatter better than a fork with stiction.

    Wasn’t all this tried at the Paris–Roubaix cobbles?


    1. What, by Rock Shox 25 years ago? I suppose, but there have been one or two innovations that may make it more viable today.
      I for one look forward to our suspension road bikes. It isn’t for smooth roads, it’s for rough stuff where just tires aren’t enough.

  4. Ok, so … that is what a MTB was in the 90s or … originally…
    So the young generation realizes that you can ride flat and uphill and you don´t need 160mm of suspension.
    What more can I do with a “gravel adv bike”, what I coundn´t do with my 26″ light tripple chainring hardtail ?

    And, the fork on the picture looks heavy, heavy, heavy.
    If it´s under 1kg, and for sure it´s not, we can talk about it.

    1. A pound or two added is less than a 1% increase in total weight. Have a hard time believing that’s going to make a big difference.

  5. If you are not interested fine, but I for one am looking forward to trying this. The future of this type of ridding has some sort of suspension on the bike. Yes you can ride with out it, just as you can ride a ridged SS, it’s about options for those who see the benefit. And yet it has been done before, no one said Fox was the first. If I remember correctly the RS won Paris–Roubaix.The more options like this the better.

  6. Well, if you take a 6,7kg Cyclocross bike, you add discbrakes, then you are at 7,5 plus a suspension fork you are at 8,3 plus bigger tires you are on 9kg.
    I don´t see the benefit, but sure for some out there, there are benefits.
    I instead take my MTB…which is often lighter than your gravel bikes … 😉

    I like the idea of a suspension fork, as long as it is light. We will see, but if weights 1,5 or 1,6 kg, where is just no reason for it.
    I experimented with a RS SID 26″ on a roadbike years ago, that fork hat 1,2kg, and if it had a little bit more tire clearance and a lock out, it would have been a lot of fun.

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