Could This Controversial Motorcycle Tech Turn Mountain Biking on Its Head?

If you keep up with motorcycle news (on, say, Gear Patrol), you’ve no doubt seen your fair share of bikes with USD (aka upside-down aka inverted) forks. 

While it sometimes feel like brands invert forks just because it sounds and looks cool, moto geeks would argue there’s a performance benefit in the form of greater responsiveness, particularly when it comes to off-road bikes. 

Fox

The folks over at Fox, a premium maker of suspension products for a variety of vehicles but mainly mountain bikes, clearly see the logic.

How else to explain the brand’s hot new enduro racing-focused product, an inverted single crown fork called Podium?

But can it really deliver on Fox’s promise of an “unfair advantage”? Let’s take a closer look.

Flipping the script

It’s worth noting that Fox is not the first to try this approach, as brands like Marzocchi, RockShox and even Fox itself have experimented with inverted forks in the past.

That said, the reasons they are somewhat controversial in the moto world — limited benefit versus being trickier to service and more likely to spew oil on your brake pads and front tire if the seal breaks — feel less applicable in the MTB space.

And as Bike Rumor points out, Fox’s product is backed by research with a prototype on their two-axis testing rig and extensive rider feedback during development.

So what exactly does flipping the fork upside down accomplish? 

Though the brand did not originally intend to go inverted, doing so significantly reduces friction, one of Fox’s major goals when designing the fork, along with enabling riders to push harder and with more confidence. 

Fox

The big upsides here are not only the the ability to better control friction using dampers but also increased stiffness on the front end.

That’s due to the fact that the stronger, outer telescoping section of the fork is closer to the source of impact (aka the ground). This greater resistance to deflection translates to better responsiveness. 

So, an inverted fork can respond to and bounce back from the vicissitudes of uneven terrain (aka bumps) quickly and efficiently. Hence its popularity with off-road bikes and now mountain bikes.

Fine tuned for flow

In the case of the Podium, Fox experimented with a number of axles to find something torsionally stiff enough, which ended up being a 20×110 Boost thru axle.

Fox tried increasingly stiff alloys before settling on steel with a medium level of stiffness that riders said hit the sweet spot. 

Fox

Without getting too technical, Fox also repositioned the bushing to enable the compression to get smoother the deeper you sink into the travel. 

In other words, even when you heavily engage the shock, the ride stays steady.

One other major point worth noting is that when it comes to weight, Fox did not discount it but did not top-line prioritize it either. 

Fox

The brand has learned that shaving grams loses its luster if it comes at the sacrifice of performance.

They’re banking on the notion that riders won’t sweat the fact that the Podium weighs some 17 ounces more than the Fox 38 — especially if it lands them on an actual podium sometime soon.

Availability and pricing

The Fox Podium Factory is available now in 170mm and 160mm travel options for $1,999.

Fox

Fox Podium Factory

• $1,999 at Fox

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