With the two biggest names in bicycle suspension—Fox and RockShox—bringing new gravel suspension forks to market, you probably have many questions. Like: “How much do they weigh?” and “Can I install one on my bike?” and “What will it do to my bike?” We’ve answered all those questions and more below. If you have other questions about gravel suspension not answered here, send an email to gear@bicycling.com.

Can I install a gravel suspension fork on my bike?

Before you can even consider what might happen to your bike if you install the suspension fork, you need to determine if you can even install the fork into your existing frame. The Fox 32TC and RockShox Rudy only come with a 1-1/8-inch upper to a 1-1/2-inch lower tapered steerer, so your bike will need a headtube compatible with that standard. (RockShox makes custom forks for Canyon that fit the Grizl’s1 ¼-inch to 1 ½-inch steerer, but those forks are not available aftermarket.

untitled cycles composition
If it’ll work with your frame, a suspension fork will make your gravel bike smoother and faster.
Trevor Raab

But even if you can physically fit a suspension fork into your frame, that’s not a guarantee it’s okay to run a gravel fork. A suspension fork is a longer lever, increasing the forces on the head tube beyond what the designers considered in the development and engineering of the frame. I first installed my Fox 32 TC test fork on a Trek Checkpoint 9.9 SLR, but when I shared a picture with someone at Trek, they wrote back and said, “We don’t recommend the use of a suspension fork on the SLR. This is due to frontal energy capacity of the frames – longer fork equal more energy in a curb-type impact.” So, you should check with the frame’s manufacturer to make sure your frame can handle the force of a longer fork.

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Your existing front brake hose may be too short because a gravel suspension fork is longer than most rigid gravel forks. Unfortunately, you’ll need a new hose, which means you’ll need to fill and bleed your braking system and re-wrap your handlebars.

What will installing a gravel suspension fork do to my bike?

Assuming you clear the hurdles above, a suspension fork is longer than a typical rigid gravel fork, creating a few items to consider.

A longer fork raises the bike’s front end and changes its steering geometry. I’ll use the new Specialized Crux as an example: The stock fork’s axle-to-crown length is 401mm: The Fox 32 TC’s axle-to-crown is 435.5mm (40mm travel) or 445.5mm (50mm travel). Subtract about 20% travel for sag, and the 32TC is 26.5mm or 34.5mm longer than the Crux’s stock fork.

specialized crux
The Specialized Crux is an amazing gravel bike. But not for a gravel suspension fork.
Trevor Raab

A 20mm increase in fork length reduces head angle by about one degree. Calculating this out a bit, a 54cm Crux has a 71.5-degree head angle, resulting in 67mm of trail with its stock fork (401mm axle to crown and 50mm offset). With a 40mm-travel and 50mm offset 32 TC installed, the Crux’s (with the fork at sag/ride height) head angle would go from 71.5 to 70.25 degrees, and the trail would go from 67mm to around 75mm. Use the TC’s shorter, 45mm, offset option, and the head angle remains the same, but the trail jumps to 80mm. More trail usually means heavier/slower steering and a more stable feel. If your head isn’t hurting enough, consider that a suspension fork’s length constantly changes as it cycles through its travel, which means head angle and trail also change as the fork goes up and down.

Steering geometry isn’t the only thing that changes when adding a longer fork. Increasing fork length will also raise a bike’s bottom bracket and lengthen its wheelbase, altering its handling. Add a longer suspension fork to your bike, and you can expect its steering to feel heavier and slower, and the bike will feel more stable. This isn’t necessarily a bad thing—you may even prefer the handling with the longer fork. And humans are adaptable: Your bike will feel different at first, but you’ll quickly acclimatize to it.

Fit also changes. A longer fork slackens the seat tube angle, increases stack, and shortens reach. Typically, you can offset reach and stack changes by removing a head tube spacer and dropping the stem or by changing stem angle and/or length. But these changes will not correct steering feel and bike handling.

fox 32 tc gravel suspension fork
The Fox 32 TC weighs 1265 grams on our scale. That’s about 1.5 pounds more than a rigid gravel fork.
Matt Phillips

How much do gravel suspension forks weigh?

The top-of-the-line Fox AX Taper Cast Factory weighs 1,265 grams. A RockShox Rudy comes in around 1,290 grams. That’s quite a bit heavier than a rigid gravel fork. Enve’s Gravel Disc fork, for example, weighs around 530 grams. That’s a 735 gram, or about 1.6 pounds, difference. That’s a lot. So if you’re very concerned about weight, you may want to sit out this first generation of gravel-specific suspension forks. But expect fork weights to come down with future generations.

How aerodynamic are gravel suspension forks?

We’ve not seen any definitive wind tunnel data, but gravel suspension forks have larger legs, larger crowns, and more frontal area than rigid forks, suggesting more significant drag. Perhaps someday we’ll see aero gravel suspension forks, but that day seems a long way off.

fox 32 tc gravel suspension fork
Gravel forks: Not aerodynamic.
Matt Phillips

Can I mount anything to a gravel suspension fork?

Both the Fox and RockShox forks have fender mounts. But they do not have any rack mounts or mounts for a bottle or cargo cages. So if you want to carry additional cargo on your gravel suspension fork, you’ll need to use straps or clamps but be warned that they’ll mar the forks finish and may void its warranty.

What Gravel Frames are suspension ready?

You have a few options if you’re itching to get on a 32 TC or Rudy as soon as possible. One is to just shove it in an existing frame (assuming a compatible head tube), deal with the handling and fit changes, and hope the frame can take the increased load of the longer fork. That’s not a great option, though.

Another option is to work with a custom builder and have them build you a bike around a longer suspension fork. You’ll get a sweet bike, but an expensive one, and you’ll need to wait a while.

If you’re looking for a stock suspension-ready gravel frame, your options are limited. Ideally, you’ll want to find a gravel frame designed around a fork with a 420mm to 430mm axle to crown length. But I can tell you there aren’t many—I did a lot of research trying to find a suspension-ready frame to install my test fork into, and I dug up only a few options.

fox 32 tc gravel suspension fork
Otso’s Waheela C is suspension ready.
Matt Phillips

I eventually wound up with Otso’s Waheela C. Its rigid fork has a 420mm axle to crown length (47mm offset), which is 7mm shorter than a 40mm travel 32TC at sag. I’ve noticed little difference in fit or the steering feel of the bike with either the rigid fork or the 32 TC. This frame also has dropper post compatibility, excellent tire clearance, and adjustable geometry with chips in the rear dropout. I am absolutely in love with this frame with the 32TC on the front: I’ll post a review of the bike late this month.

Cannondale’s Topstone is another option. Again, no surprise here as some models come with Cannondale’s Lefty Oliver suspension fork (420mm axle-to-crown for the 700c-compatible fork).

Lauf’s True Grit frame is a more boutique option, though it’s designed around Lauf’s 30mm travel True Grit fork, which has a 412mm effective length (418mm minus six millimeters of sag), so adding the 32TC to this bike will raise the front end a bit.

Salsa recently launched the Stormchaser SUS, an aluminum bike that comes stock with a 40mm travel RockShox Rudy. Salsa sells this frameset, with 420mm axle to crown rigid fork, for $1,299.

And if you’re looking to go full tilt, Niner’s MCR full suspension gravel bike is, of course, suspension-corrected and suspension ready.

evil chamois hagar
Evil’s Chamois Hagar seems like the perfect platform for a gravel suspension fork. But it may not be the best choice.
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Evil’s Chamois Hagar seems like a natural platform for a gravel suspension fork with its mountain-bike-influenced geometry. But while the CH’s is built around a 428mm long fork, the stock fork’s offset is 57mm. With the Fox and RockShox gravel forks having a maximum of 50mm of offset, the Hagar’s already generous 93mm trail—typical gravel bikes have 60-70mm trail—will get even longer, and the result might be a gravel bike that’s too stable, and therefore feels sluggish. I did check in with Evil, and they told me that they’ve ridden the Chamois Hagar with suspension forks and not found the handling change detrimental. However, they did say that the size and shape of Fox’s crown doesn’t blend well with the frame, “These new gravel forks look like a toothpick sticking off the front of a Harley when mounted to the Chamois Hagar.”

niner mcr
Are more full suspeniosn gravel bikes like the Niner MCR on the horizon? Maybe.
Trevor Raab

Gravel Suspension Forks—Chicken or Egg?

There is a reasonably simple way to make it so replacing a gravel bike’s rigid fork with a suspension fork doesn’t alter its handling or fit and ensures the frame can take the loads imparted by a longer fork: Design the bike around a rigid fork that’s about the same length as a suspension fork. This is called suspension ready or suspension corrected geometry. At this moment, however, there are not many suspension-ready gravel frames.

Gravel suspension forks are, all things considered, a new thing—with unknown customer demand—and weren’t on most designers’ radar when their current gravel frames were in development. And because gravel suspension forks (mostly) didn’t exist, there were no specifications to design around. So, frames were planned around the shortest possible forks—just long enough to get the required tire clearance— which is the most efficient design for a rigid fork.

With the two most prominent players in bicycle suspension—Fox and RockShox—bringing gravel suspension forks to market, designers can take longer forks into account when designing their upcoming gravel frames. I suspect we’ll see several gravel bikes launching in the reasonably near future that either come stock with a 32TC or Rudy or have longer stock rigid forks so the customer can swap in a suspension fork without altering the frame’s fit and geometry.

Headshot of Matt Phillips
Matt Phillips
Senior Test Editor, Bicycling

A gear editor for his entire career, Matt’s journey to becoming a leading cycling tech journalist started in 1995, and he’s been at it ever since; likely riding more cycling equipment than anyone on the planet along the way. Previous to his time with Bicycling, Matt worked in bike shops as a service manager, mechanic, and sales person. Based in Durango, Colorado, he enjoys riding and testing any and all kinds of bikes, so you’re just as likely to see him on a road bike dressed in Lycra at a Tuesday night worlds ride as you are to find him dressed in a full face helmet and pads riding a bike park on an enduro bike. He doesn’t race often, but he’s game for anything; having entered road races, criteriums, trials competitions, dual slalom, downhill races, enduros, stage races, short track, time trials, and gran fondos. Next up on his to-do list: a multi day bikepacking trip, and an e-bike race.