Spotted: Fox Gravel Fork Prototype

Maybe it’s a deliberate tease, or maybe the sun and heat of Moab has gone to Geoff Kabush’s head, but his Instagram shows a new Fox gravel fork that we’re pretty sure isn’t supposed to be out in the wild yet. We’ve done our best with hi tech image enhancement techniques to have a closer look.

The biggest suggestion that this is a leak rather than a tease comes in the form of the reverse arch fork. Manitou currently holds the worldwide patent on this, but it’s due to expire in October this year.

Covered in Fox RAD stickers – this is Racing Application Development, effectively a prototyping and research arm of Fox that looks at mods and adaptations for pro racers – there is nothing to say what diameter stanchions it might be. However, Fox has had a gravel fork before – the Fox AX. This was itself a modified Fox 32 fork with travel reduced to 40mm that’s still out and about available to buy. We can only assume that Fox is hoping to bring some more gravel specific refinements to the design with this latest fork.

Who knows what travel this might be? ‘Not very many millimetres’ is all we can say for sure, though a guess that it’ll match the AX fork’s 40mm would seem fairly educated, given that the amount of exposed stanchion is about the size of Kabush’s 40mm front tyre. Assuming the legal eagles at Manitou deem that the cost of defending the patent in its final months is greater than is worth it, we might expect the reverse arch to make it through to production, offering a lighter build than would be possible with a forward arch. Weight savings look likely on the fork lowers too – these appear to have some tapering, which would again remove material from the construction and allow a lower weight. (The lower shape reminds us of the old RockShox Mag21 fork – and who remembers the RockShox Ruby, eh? As ridden to Paris Roubaix victory back in the old days of rim brakes on road bikes.)

It’s hard to be sure from the angle of the photos available, but it looks as though the crown of the fork may be dropped a little compared to on the AX or Fox 32. If you imagine the lockout and air valve are the shoulders, then this Fox RAD fork looks to be slouching like a teenager. That would give clearance for the fork on a wider range of frames than is possible with the Fox AX, assuming that rear arch doesn’t add more problems than it solves.

That’s about all we can see for now. Will it have a carbon crown? Fox hasn’t bothered in the past, but this is the different world of gravel! We await further details with interest – though we suspect we might be waiting a while. But what would it take for you to want to fit one of these to your gravel bike? How light would it need to be to be worth the trade off compared to some bigger tyres? And at what point do you just reach for a carbon hardtail with top end XC fork?