We have been seeing a lot of cyclocross and gravel bikes equipped with rise bars instead of drop bars, but this doesn’t make a lot of sense. Cyclocross bike geometry is designed for drop bars, with the reach of the bikes designed into the bars. If you replace a drop bar in favor of an MTB flat or rise bar, you’re essentially ending up with a very upright hybrid bike that needs a lengthy throwback XC stem to fit correctly.
If you prefer to run a fully rigid bike with rise or flat bars for long-distance multi-surface rides, it makes a lot more sense to come at things from the other side of the fence, and start with a 29″ MTB frame. Not only does that give you every option under the sun in regards to tire choice, but they’re actually designed for riding in the dirt. (there’s also the question of safety, on riding a bike that is capable of more rugged off road use)
While independent frame builders have been leading this charge for some time, one of the easiest ways to go about creating the ultimate flat bar/hybrid/gravel bike is to replace the suspension fork on an off the shelf XC 29″ MTB with a rigid fork.
For those looking to make the upgrade, we recommend selecting a fork with boost hub spacing for maximum versatility. Most wheels can be adapted to boost with a spacer kit and re-dishing the wheel, and it leaves you with the most options down the road. Of course, we’re hardcore bike geeks that are often experimenting and tinkering with different setups.
Whiskey Parts Co. No. 9 — $549.99
Whiskey Parts offers a full range of rigid forks for dirt use, whether its Fat, MTB, or CX/Gravel. In fact, for MTB applications alone there are three options available, depending on the amount of tire clearance required, as well as ride height (axle to crown).
With clearance for up to a 3.0″ tire and tall enough to replace 120mm to 130mm travel suspension forks (maintaining that geo that brought you over to the MTB side) the No. 9 MTB Boost LT fork is our pick from the lineup, as we tend to upfork our bikes already, and the longer axle to crown would come closer to maintaining the ride height we’re already fond of. It features a tapered steerer and a fork length of 50mm, boost spacing and 51mm rake.
- Axle-to-crown: 500 mm
- Rake: 51
- Material: Raw UD Carbon
- Steerer: 280mm, 1-1/2” tapered
- Tire Clearance: 29” x 3”
- Listed weight: 680g.
Enve MTB Carbon 29″ Fork — $625
At $625, the Enve carbon fork is the highest priced fork on the list but makes a compelling case for declaring itself the leader of the pack with a list of unique features. With its reversible dropout chips, you can tune the fork rake to your preferences adding significant value. It also includes a removable mini carbon fender. (many rigid forks can be challenging to add a fork-mounted fender) Riders also have the option of running 140, 160, or 180mm disc brake rotors.
- Axle-to-crown: 470 mm
- Rake: 44, 52
- Material: 100% Carbon Fiber
- Steerer: 300, 1-1/2” tapered
- Tire Clearance: 29” x 3.4”
- Listed weight: 686g., 711g (w/ fender)
Salsa is known for bike packing and gravel solutions. They have one of the widest selections of rigid forks at a wide range of price points.
- High-modulus carbon fiber construction
- Tapered 1-1/8″ to 1-1/2″ steerer tube
- Axle-to-crown: 483mm
- Fork rake: 51mm
- 110 x 15mm thru-axle
- 180mm maximum rotor size
- 27.5 x 2.8–3.0″ or 29 x 2.2–3.0″ tire fit
- Dual sets of Three-Pack mounts on each fork leg for Anything Cages or water bottles
- Mid-blade mounts for low rider racks
Niner Boost RDO fork — $550
Full carbon construction, boost spacing and clearance for 29 x 3.0 tires make the Niner RDO MTB fork a contender for your rigid fork upgrades. Like the Salsa and Whiskey options, it’s bike packing ready with rack mounts.
- Axle to crown: 490mm
- 180mm maximum rotor size
- 51 mm rake
- Boost spacing
MRP Rock Solid Carbon — $420
Our pick from the MRP line up is the model with the tapered 490 length, which is the most inline with our suspension fork. Available in both straight and tapered steerers.
- WEIGHT: 1.6 lbs. / 725 g
- 1-1/8″ or Tapered (1.5 – 1.125″)
- OFFSET: 44MM QR, 42mm 15x100mm
- 9x100mm QR or 15x100mm
- AXLE-TO-CROWN (length): 445, 465, or 490mm
Available in a tapered or non-tapered model, the WCS Carbon Mountain Fork is available for 27.5″ and 29″ wheels.
- Full carbon construction: crown, steerer and drop out
- Post-mount brake for 160mm rotor
- Steerer Length: 300mm
- Steerer Diameter: 1-1/8”
- Rake: 42mm
- Brake Mount: Post
- Axle-Crown: 459mm
- Matte UD carbon finish
- Weight: 615g
Carver Trail 490 Carbon Fork — $299
One of the best values in carbon rigid MTB forks, the Trail 490 is suspension corrected and our top picks when it comes to bang for the buck, but it isn’t quite clear how large of a tire you can run. There is a suspicious lack of product reviews available online as well, which is never positive.
- 29’er, 650B compatible
- Post mount disc
- 15×100 or 15×110
- Full carbon 270mm steerer
- Tapered 1.5″ to 1-1/8″ steerer
- 490mm axle to crown
- Clearance for 29 x 2.35mm tire
- 45mm Fork offset
Surly Krampus Fork – $110-175
Riders looking to test the waters without spending a lot of dough are probably already familiar with the Surly brand. This chromoly rigid fork option is available in quick release and boost options with tire clearance of up to 29″ x 3″ with a 483mm axle-to-crown. The 1 1/8″ steerer isn’t a big hurdle if you’re running a Cane Creek headset (the 40 is our favorite headset for the money hands down) as you’d simply need a crown race adapter.
- Axle-to-crown: 420mm
- Offset: 47
- Steerer: 285mm, 1-1/8” straight
- Tire Clearance: up to 29” x 3”
- Weight: 2.6 lbs. (1180g)
The Krampus also includes like a million braze-ons should you want to add racks, fenders, or bottle mounts for bike packing.
Salsa Cromoto Grande — $130-$209
A more budget-friendly option to their carbon offering, the CroMoto Grande is available in QR or non-boost. Starting at $130 for the straight steerer, a tapered option adds almost double to the asking price.
- Axle-to-Crown Length: 483mm
- Material: CroMoly
- Offset: 45mm
- Crown Race: 39.7mm
- Front Axle Type: 15mm thru-axle
- Front Hub Spacing: 100mm
Scary Generic Fork on Amazon.com – $72- $129
Who knows what you gonna get? Except you probably want to always run a full-face helmet going with one of these in the event it fails and you land on your chin. I think I’d trust Alibaba more, but .. no.
- Stunning lightweight Al mountain bike fork with 7075 Al steerer, 7050 Al stanchions and forged 6061 Al dropouts
- This fork is disc brake specific
- For a V-brake compatible fork see CC-F0225 for carbon or CC-F0125 for Al
- Rigorously tested to EN and DIN standards
- This alloy one is probably stronger than a generic crabon one, right?
Looking to try a rigid fork? Our retail partner Jenson USA has one of the best selections of rigid MTB forks around.
Post update: originally this post focused on highlighting 5 forks… but we couldn’t stop the dive down the rabbit hole. (post titled updated) Want to see the fork we went with for Inga’s BMC? View the post here: 29″ MTB to Gravel Conversion