Forge + Bond F+B 25 GR review: Comfortable carbon wheels made to be recyclable

FusionFiber has made a splash in the carbon wheel market, particularly for mountain bikes and gravel bikes. The claims made by its creator, CSS Composites, are heady: lighter, stronger, and 100 percent recyclable, a huge claim in the carbon fiber world. “FusionFiber” has surfaced on carbon wheels used by Chris King, Revel, Atomik, Evil, and others.

And now, CSS Composites has launched its own brand of complete wheelsets called Forge+Bond. 

The FB 25 GR wheels pictured came taped for tubeless installation using included Forge+Bond-branded tubeless valves.

The Utah-based company has launched with two wheels. There’s an enduro-centric wheel called the F+B 30 EM 29”, and a carbon gravel wheelset called the Forge+Bond F+B 25 GR. Both are based around their carbon rim expertise, but rather than using a standard epoxy and thermoset form of carbon fiber, these rims use a thermoplastic carbon fiber. 

Forge+Bond’s wheels might look like a traditional carbon wheelset online or at a quick glance. But a closer inspection — and riding the wheels — reveals there is more to the package than meets the eye.

What is FusionFiber, and why does it matter?

We can’t talk about why FusionFiber is an interesting development in carbon fiber wheels without talking about how standard carbon fiber is produced.

Traditional carbon fiber consists of literal filaments of carbon fiber, which have a hand feel similar to fine hair. These filaments are threaded together like thread to make a string. Just as a bunch of string is threaded together to make rope, carbon fiber can be woven together to make something strong. 

These carbon fiber strands are then threaded together to create a weave, similar to how string can be woven into fabric. The difference here is that carbon fibers aren’t held together purely based on tension and a good stitch, but by some sort of bonding agent, generally an epoxy resin.

Epoxy resin is permanently set into place once cured by heat. Break that resin, and there’s not much you can do, so a cracked piece of carbon can be a problem. There’s also the problem of recyclability; most carbon fiber can be recycled, but not in a way that is economical or energy efficient. This leads to broken carbon fiber sitting in landfills.

The wheels proudly note their FusionFiber construction on one side and a “Made in the USA” sticker on the other.

FusionFiber uses a thermoplastic resin that isn’t permanently set by heat.

In theory – and by CCS’s claims – FusionFiber’s resin choice means a damaged piece of carbon fiber can be grounded down, melted, and remade into another carbon fiber component using a thermoplastic resin over and over. So not immediately better for the environment, but legitimate recyclability is a massive step in the right direction.

There are other claims to greatness for FusionFiber. Thermoplastic resin means the carbon fiber construction itself is said to be more impact-resistant than traditional carbon construction, citing that their wheels are tested to withstand a minimum of 275 percent of the UCI standard for impact resistance. 

FusionFiber’s unique construction also affords a claim of a 50 percent or greater increase in vertical damping while maintaining flexibility. Translation: the carbon construction is said to improve the ride quality and dampen vibrations without being a noodly mess in the corners or when putting down the power.

Forge+Bond uses a hookless bead construction on all of their rims.

Okay, so why is it that thermoplastics are only hopping now on the scene? 

Well, the tooling is expensive. Developing the tech itself is expensive. CSS Composites says they don’t only make carbon for bicycle components; they also do forged carbon for aerospace, performance automotive, and industrial applications. They already had the tooling and know-how, so carbon wheel investment made sense.

This isn’t the first time we’ve seen thermoplastics in the bicycle world. Guerilla Gravity has been doing it for about three years with their Revved carbon, touting the same recyclability, minimal sanding work, and less waste.

Forge+Carbon’s first introduction to using recycled carbon fiber will be a tire lever that comes with each wheelset. Expect more applications of recycled carbon fiber down the line for bike components and accessories.

F+B 25 GR build details

The F+B 25 GR rim shape is similar to the likes of an ENVE G23, Reynolds G700, or other shallow carbon fiber gravel wheels tuned for rider comfort and strength rather than aero. Its shape is unique to Forge+Bond, and different from the likes of the Chris King GRD23 wheelset which uses CSS Composites to make its own rims.

These rims use something the company calls NXS design, which adds material around spoke holes to strengthen them. It isn’t noticeable from a distance, but up close and in the light, you start to see that the rim itself has a bit of a wave to it. This is the case for both the enduro rim and the gravel rim we have here.

The spoke hole reinforcement isn’t immediately obvious, but is an example of how much care was put into the rim design.

The rim design itself is contemporary. A 25 mm internal rim width is paired to a wider 31.4 mm external width with up to a 3.2 mm thick beadwall and a shallow 25 mm rim depth. All Forge+Bond wheels are hookless bead and are designed to only work with tubeless tires.

Forge+Bond seemed to build these wheels with an eye toward longevity by using standard components throughout. At the center of the F+B 25 GR wheelset is the Industry Nine Classic Torch hub. 24 spokes are laced two-cross with Sapim CX-Ray bladed spokes, though my early-access wheelset came with Sapim Race double-butted spokes. Either way, these spokes are anchored by easily-accessible spoke nipples. 

Industry Nine Classic Torch hubs are an easy choice. I’d love for Forge+Bond to expand to include their array of ano colors too rather than a flat black.

All F+B 25 GR wheels use Industry Nine’s stainless steel bearings. Hubs are only available using either Shimano HG Road or SRAM XDR freehub options. 

Claimed weight for the wheelset is 1510 grams. Actual weight for my test wheelset was 1560 grams with a Shimano HG freehub body, tubeless tape installed, and a pair of valve stems that come with the wheelset. Swap to a CX-Ray bladed spoke and I have no doubts that you’d hit that claimed weight mark easily.

F+B 25 GR riding impressions

The F+B 25 GR wheels are standouts on paper but only if you’re looking at the promises made by the unique carbon fiber construction. Otherwise, they don’t particularly stand out when purely looking at a spec sheet. Numbers rarely tell the whole story, however, and that is the case here.

Simply put, the F+B 25 GR wheelset has a distinctively smooth ride quality compared to just about any other wheelset I’ve ridden. I mean that in the best way.

Ready to roll. Or stay still. The wheels were very obedient in my time with them.

Some gravel wheels are obviously stiff, responsive when you put the pedals down, corner with precision, and require you to really dial in your tire pressure to ensure you don’t get rattled down the road. Others are smoother in feel, great for finding grip but perhaps don’t feel quite as quick as other wheels.

These wheels calm down the ride. Vibrations are damped noticeably, and you tend to feel like the wheels glide over pavement rather than bouncing between each crack, divot, or rock on a trail or gravel road. I didn’t feel it quite as much on a bike that already had some sort of vibration damping, but I felt a massive difference on stiffer gravel bikes without any built-in vibration damping.

I tried to figure out if it was flex I was feeling, and I don’t quite think it was. Sapim’s double-butted spokes aren’t as stiff as a bladed option. That said, I have a hard time believing it was purely spokes as I didn’t feel the wheels were lacking in stiffness while cornering on singletrack, which leads me to believe the rim is doing much of that heavy lifting. 

It was a tough day for lighting here in San Antonio, but the carbon with a clear powdercoat looks fantastic.

The closest thing I could think of is that it feels like your tire pressure is 5-10 PSI lower than you’d usually run it. The difference is that when you stood up to pedal, either to sprint or to get up a climb, the floatiness one would find with low tire pressure wasn’t there.

Running a low tire pressure on a gravel bike has a number of downsides, one of which is vagueness while cornering. The F+B 25 GR wheels had none of that, feeling plenty planted and secure cornering through singletrack. 

Industry Nine makes a fantastic hub, and the Torch Classic hub is one of my favorites. The six-pawl hubs offer quick engagement. Further, the rest of the hub has stout construction and is relatively simple to maintain. The same goes with the Sapim CX-Ray spoke choice. No qualms overall, though folks who prefer quiet hubs may want to look elsewhere.

These wheels eschew the bladed spokes one might expect at this price point for Sapim Race double-butted spokes. I am sure the wheels could cut another 50 grams of weight by going in that direction, but they might lose some of their impressive ride smoothness.

Tubeless setup was a breeze as well. Wheels come pre-taped from the factory and with Forge+Bond’s own tubeless valves. The wheels set up easily with a floor pump with an array of gravel tires both new and old, though I did have to use levers for every new tire I set up. 

Build quality was excellent overall, a great sign for a new company like Forge+Bond. There was even spoke tension everywhere, and the wheels stayed round through testing. And because the hub uses standard J-bend spokes and external spoke nipples, maintenance and replacement should be a cinch.

Forge+Bond wheels feature a lifetime warranty that protects against structural defects in material or workmanship for the original owner. There is also a lifetime crash replacement policy, though they don’t specify what that entails. One thing they made clear though? They want your old wheel back so they could recycle the carbon to make something else out of it.

Big ups to the valve stem cover, which doubles as a tubeless valve core remover.

I should note that a good alloy wheelset isn’t much heavier than these wheels. They won’t ride as stiff as a carbon wheel too, and with a tire insert, can offer some of the grip and comfort I experienced here. And of course, an alloy rim can be recycled too depending on where you live.

I still think these were better. Compared to a standard alloy wheelset like an Industry Nine 1/1 GRCX, the Forge+Bond wheels were noticeably more planted-feeling across chunky gravel and singletrack. There may not be a massive lower rotational weight advantage either, but the F+B 25 GR wheels were more willing to get up to speed than the alloy wheels.

You’d expect that kind of performance from a high-end carbon gravel wheelset, and these delivered.

These Kenda Allvium Pro 40 mm tires mounted easily with a floor pump. Didn’t even need to remove the valve core!

Conclusion

A smooth gravel bike is a fast gravel bike, and while these wheels aren’t particularly aerodynamic, they are one of the smoothest-riding gravel wheels I’ve used. The carbon wheels offer fantastic ride quality over rough and high-vibration terrain, are easy to service, and while not especially lightweight, aren’t terribly heavy. Then there’s the potential recyclability that brings massive points for me.

I’m sure that someone will look at these wheels and point to some sort of direct-to-consumer alternative that’s half the price. They’d be right, as there are a number of options that will do a great job. But none of them quite have the intangibles and off-paper positives that these wheels do. The smooth ride quality, lower weight, additional strength, and potential recyclability make these wheels standouts.

Price, Forge+Bond F+B 25 GR wheels: US$2,650 / AU$3,990 / £3,000 / €3,100

forgeandbond.com

This gravel wheelset is proudly made in Utah.