Today, yet another brand is releasing thermoplastic carbon rims manufactured in Utah by CSS Composites. But unlike Revel or Chris King or Evil who launched house-branded CSS-made rims in 2020 and 2021, respectively, FORGE+BOND is actually a new division of CSS itself. This product launch represents the next step in the development of CSS’ fully recyclable FusionFiber™ material and manufacturing process. Travis Engel spent some time with the founders riding bikes and taking notes, and he has things to say.

A lot of bike brands don’t actually make their own stuff. It’s one of the industry’s dirty little secrets. Sure, everyone designs their own stuff (or, so we assume) but many of our branded frames and components were actually born in effectively nameless factories that are often juggling orders from multiple competing clients. And despite how I’m making it sound, this is a good thing. It’s more time—and cost—efficient, and it puts the manufacturing in the hands of the real experts. I mean, WTB doesn’t own and operate farms of injection molding machines. They leave that to Velo Enterprise Co. Ltd.

But what if we’re talking about a field with much more room for innovation than injection-molded saddles? One still striving to reach its potential? That type of nameless factory is probably doing some pretty cool stuff behind the scenes. Stuff that may be worthy of lifting the veil of anonymity and bearing its own name.

FORGE+BOND was the name chosen by a bike-focused, consumer-facing supergroup emerging today out of Utah carbon tech firm, CSS Composites. CSS manufactures rims for Revel Wheels and Evil Loopholes, and is the developer of a novel concept in carbon called FusionFiber. In a nutshell, FusionFiber centers around bonding carbon fiber using thermoplastic resin instead of traditional “thermoset” epoxy resin. Think hot glue instead of super glue. Like hot glue, thermoplastic resin remains slightly compliant once it’s cooled. It can make structures that are more impact-resistant and better damped than thermoset resin, positioning it as an ideal material for rims. And it’s been great for Revel and Evil, but those outside brands aren’t great places for CSS to “push the boundaries” of FusionFiber. It’d be like Kumail Nanjiani workshopping stand-up material on the set of The Eternals. The mountain and gravel wheels launching today are the result of FORGE+BOND’s extensive workshopping.

We’ve ridden them, and we have thoughts, but we’ll talk about that later. There’s more to unpack than vertical compliance and lateral stiffness.

Waste Nothing

For those unfamiliar with the promises made by thermoplastic composites like CSS’s FusionFiber or Guerrilla Gravity’s Revved, much of the narrative focuses on its environmental benefits. It can be recycled, though not into a(nother) rim or a frame, or other carbon product we usually think of in the cycling industry. During recycling, the long carbon strands that make such thin-walled hollow structures so strong get chopped down to pieces, thereby reducing the resiliency. But heat up those pieces enough to melt the resin, and they can become almost any object you’d form in a mold.

Since FusionFiber hit the bike world, the only object we’ve seen so far are these tire levers. They’ve dropped in and out of consumer availability over the past three years, but a pair will be shipping alongside every FORGE+BOND wheelset. And they’re pretty impressive. As one was passed around, I took my turn as an opportunity to (what else) try to break it. Putting all my strength into bending the six-inch lever, it would not yield. The short fibers help reinforce the already tough resin. Still, recycled FusionFiber seems like it’s destined for more “important” products than tire levers. Stems, saddle bases, aftermarket brake lever blades, dropouts for a potential FusionFiber frame. I have no idea. I’m not an engineer. I pressed the FORGE+BOND folks about how that’s going, and they’re clearly working on it. It’s just a matter of assessing the demands of a given product and, I assume, the economics of producing it under the same roof as their high-end carbon rims.

FusionFiber components don’t require intense post-mold sanding and finishing or the powerful refrigerators necessary for storing thermoset carbon, which has a finite shelf life. The manufacturing process behind thermoplastic components can be quicker, and much of it can be automated. That helps make this type of carbon fiber more cost-effective to produce in the U.S., which for domestic consumers, means far fewer resources wasted on shipping. That goes double for CSS, who uses U.S.-sourced raw materials for all their rims.

This stuff isn’t exactly news, but FORGE+BOND is lifting the curtain a little (not a lot) on other details behind how FusionFiber rims are made. One clue is in the brand name itself: they are forged, then they are bonded. When making a traditional thermoset carbon rim, all the curing and compression happens at once in its heated mold. A FusionFiber rim, on the other hand, will go through multiple thermal cycles during its assembly. One of those cycles resembles forging, in that the carbon panels are compressed in a metal die. That process individually forms multiple “flat” components of the rim, which are then bonded together.

We also got some clues about the automation of FusionFiber component assembly. The device that achieves the “radial cross-ply” layup of the rim sidewalls is like an automatic playing-card dealer, sliding out pieces of pre-preg carbon in a circle with robotic precision. In part, this is done to take advantage of the benefits of thermoplastic resin, which is less sticky, flimsy and fragile at room temperature than thermoset resin. It’s predictable enough to program a robot to handle. Other aspects of assembly actually kinda have to be automated. Because heat is necessary to make the material pliable, it would be difficult to manipulate with only the protection of rubber gloves. The machines doing the layup are equipped to handle, and in some cases, apply the heat.

But this is fundamentally how all rims are made at CSS, including Revel and Evil’s. So, that begs the question: what’s different about how the new rims under the FORGE+BOND banner are made? Well … they wouldn’t tell us. But that’s normal. There’s a lot of secrecy in carbon manufacturing, especially on untrodden ground like modern thermoplastics. Basically, FORGE+BOND rims use their own industrial design, their own refined layup, and are able to make more efficient use of the material. The wheels that launch today are simply the next step in what’s possible with FusionFiber. So, let’s dive in, numbers-first.

Facts and Figures

FORGE+BOND is debuting with the F+B 30 EM mountain wheels and the F+B 25 GR gravel wheels. The 30 EM is available with either 28 or 32 spokes and, for now, is 29-inch only, but they say to “stay tuned” for news on a 27.5 version. The mountain wheels are built around Industry Nine Hydra hubs and Sapim D-Lite J-bend spokes. The rim’s inner width is 30mm, flanked by pretty thicc 4mm bead walls. They’re meant for 2.3″ to 2.6″ tires and have a bare weight of 530 grams. The complete wheelset weighs 1,884 or 1,982 grams for the 28-spoke and 32-spoke versions, respectively.

The 25 GR uses 24 J-bend Sapim CX-Ray spokes laced to Industry Nine Torch hubs. They’ve got a 25mm inner width with 3.2mm bead walls and are suited for 32 to 48c tires. The rim weighs 380 grams, and a wheelset weighs 1,510 grams.

The wheels will be available in pretty much any “modern standard” axle and freehub configuration offered on Industry Nine’s mountain and gravel hubs. They may be sold rim-only at some point, but for now it’s all or nothing. And FORGE+BOND offers the sort of comprehensive lifetime warranty that popped up years ago to help convert the skeptics. Any, any damage done to the rim by the original owner that’s not determined to be a manufacturer defect will still get concierge-level repair (rim replacement and re-lace), and all you pay is shipping. Of course, damage that did arise from a defect will be handled totally free of charge. Forever.

Another important number to cover is $2,599. That’s a bit more than the $2,200 price tag on the Hydra-equipped Revel Wheels or Evil Loopholes. Revel even offers an option with i9’s less expensive 1/1 hub for $1,800. Many of those wheels seem to be on pretty deep discount right now, but that’s true of a lot of things in the industry, so there’s not necessarily any connection to the FFORGE+BOND launch. Regardless, a fairer comparison to FORGE+BOND would seem to be with fellow Utahns (it’s a word, look it up), ENVE. Their Hydra-equipped, U.S.-made carbon enduro wheelset goes for $2,550.

Quick sidebar here: With all this automation and speed and efficiency in FusionFiber wheel manufacturing, that price tag doesn’t seem to track. Guerrilla Gravity’s thermoplastic Revved frames are more than $1,000 cheaper than North American carbon frames from Ibis or We Are One. Granted, Guerrilla Gravity frames have aluminum stays, but their approach seems to be evidence that thermoplastics can bring down the price of domestic carbon, while F+B seems to be going in the other direction. Not knowing the details of Guerrilla Gravity’s manufacturing processes or company economics, the folks at F+B weren’t able to shed any light on why this may be. But there’s a lot of intense R&D behind advancing the application of FusionFiber. For example, when someone wants to tweak the layup on a traditional thermoset carbon component, they just do it by hand. But the automated nature of FusionFiber construction means those tweaks have to be possible for the equipment to perform on a large scale, and then they have to be programmed to do it. There’s a lot of front-loaded labor in this type of endeavor. The words “trickle down” weren’t said outright, but it stands to reason that as the processes developed by F+B will be repeated on increasingly larger scales, and prices could come down in the future.

While we’re on the topic of making imperfect comparisons, the mountain and gravel rims’ 530- and 380-gram weights are more or less on par with Revel and Evil. Depending on which model you pick as a one-to-one counterpart (which none actually are), there’s around a 4% difference—sometimes heavier, sometimes lighter—in weight. But compare F+B rim weight to that of traditional thermoset rims (which I acknowledge is much more flawed than comparing FusionFiber rims), and the difference is more significant. Seemingly similar mountain and gravel rims from Hunt, Reserve, and Canadian-made We Are One are consistently, if sometimes slightly, lighter than F+B’s.

But here’s where the numbers section officially ends. I’d say that anyone looking at lighter rims as a way to gain speed and efficiency is missing something important. The ride characteristics promised by a material like FusionFiber can potentially offer more speed and efficiency than shedding weight can. It’s like when elite-level road racing finally realized that it’s often faster overall to run a 28c tire at 85 PSI than a 23c tire at 110 PSI. The world ain’t smooth, and a little give goes a long way.

So, how do they ride?

That dynamic extends to the dirt, though with some nuance. There’s more rubber, more air, and probably more suspension between you and that un-smooth world. I’ve heard some of my colleagues in the gear-review game say they can feel the added traction and overall calmness of a rim with FusionFiber’s damping qualities permeating their entire ride. But for me, it’s more about what happens in individual moments of chaos. The way I personally sense the effects of a damping-focused wheel on the trail is when the peaks of a quick series of extremely high-intensity impacts all get slightly dulled, and I can stay in just a little more control. On my personal bikes, I achieve that with alloy rims, especially now that I’m only in the gear-review game part-time and fancy carbon rims don’t show up on my desk every other week. But when these fancy carbon rims showed up, I happened to be riding a Canyon Spectral 125 test bike with DT XMC1501 wheels, which are pretty traditional and make no earth-shattering claims about comfort.

After making the swap to the new wheelset on this supportive, intentionally hard-hitting trail bike, the improvement was significant. I’m not shilling for FORGE+BOND when I say I noticed a difference as soon as I charged my first rock garden. They somehow turned the volume down just enough that I could hear the conversation I was trying to have with my handlebars. The bike would be just a little more manageable, and I was able to make rational decisions when I would otherwise just be in crisis-management mode. And I can prove I’m not shilling for F+B by saying that, for the rest of the ride, I felt no difference compared to the DT Swiss wheels or, for that matter, the alloy wheels on my very similar personal trail bike. Moderate chop that was below the redline seemed to disappear just fine, regardless of what wheels I ran.

But I think my hot take counts as testimony that the more supple material of these rims doesn’t give up an inch in their overall shred-worthy feel. And that’s a feeling I really value. Enough so that it wasn’t until years after aggressive carbon rims hit the scene that I started getting bothered by the added harshness. A light, stout carbon wheelset makes for a subtle but qualitative difference in how a bike rides. Though they damn well should for $2,600, the FORGE+BOND maintains that without compromise. I can’t say the same for the supremely comfortable single-wall Zipp 3Zero Moto rims. F+B wheels walk the tightrope of optimal feel quite nicely, even if the ride isn’t totally paradigm-shifting. But as I said, like, 1,700 goddamn words ago, there’s more to these wheels than vertical compliance and lateral stiffness.

So, what does it matter?

Look. I know that high-end carbon bike products are not the biggest problem the earth is facing. Every Wednesday night, I wheel a giant blue bin out to the curb full of many times these rims’ weight in plastic. And I just forget about it, trying to ignore what I’ve read about how little of that stuff actually gets recycled. Yes, I would love for that problem to be solved, but it is not going to be solved by the people who manufactured the parts on my bike. I want those who make the bikes I love to keep making the bikes I love. It’s what they do. I read a story about a high-quality, high-durability paved pumptrack that Velo Solutions built in Uganda, and some asshole commented about how many things they think the people in that village need before they need a pumptrack. Maybe true. But pumptracks are what Velo Solutions does. So, they did what they could. Recyclable carbon is what CSS Composites does. In fact, they do it on a far larger scale than the $2,600 bicycle wheel market. Much of their business is in commercial airlines, where composite technology is helping reduce the impact of something that actually is a big problem the earth is facing. Some folks at CSS developing FusionFiber just happened to be cyclists and saw its potential.

And though cleaning it up won’t save the world, high-end carbon waste ain’t nothin’. There’s something we don’t think about when we say “recyclable carbon.” It’s not just that our rims will get a new life after we crack a bead wall. This is kinda the fact of the show, and I probably should have said it sooner: the volume of pre-consumer material being recycled at CSS Composites is greater than the volume of post-consumer material. That includes excess carbon panels, blemishes, QC test products, and development experiments. Now, consider an overseas factory that does higher volume at lower cost. They’re likely producing even more pre-consumer waste. Think about that if it feels like the quantity of carbon you personally own seems insignificant. Maybe you’ve seen one of those viral photos of discarded carbon frames piled up behind a factory. All that stuff is gonna hit a landfill, and it’s all kinda toxic.

That’s another cool part about what FORGE+BOND and CSS are doing. Their recycling is done in-house, at least for now. I asked them why that is. I mean, as far as I know Coca Cola isn’t recycling plastic bottles at their bottling plants. But the world of thermoplastic consumer-product recycling is very new and very small. I can’t just throw my FusionFiber rim into that blue bin next to all my empty Samoas trays. And the folks at F+B wouldn’t want me to. In fact, sending back your damaged rim is a required step in getting it replaced. There’s economic value in its raw materials, and only F+B knows how to properly recycle it. So, it has to be done in-house. But also, maybe it should be. There was a time when Coke definitely was involved in the recycling process, and on a massive scale. That was back in the days of glass bottles. And the refund value was high enough at the time that there was an incentive for people to take advantage of it. There was economic value in reclaiming those bottles. It helped keep that circle from being broken by the overwhelming force of convenience.

So, no, these $2,600 wheels are not going to save the earth. But we’ve all seen the explosion in the popularity of carbon in the cycling world. We’re not going to make it go away. But we could make it happen domestically. We could make it happen more sustainably. We could make it happen cheaper. If enough of the people behind that explosion see the benefits of thinking differently, we could make it better.

Read more at FORGE+BOND