Last year, we looked into Revel Bikes
, at that time a new company started by a few industry veterans. Following the launch of two trail bikes, Revel has now released a 100% recyclable and US-made carbon rim that's manufactured in a much different way than traditional carbon bike parts. Revel is calling this method "Fusion-Fiber" technology, and it was developed by an aerospace facility in southern Utah.
Revel's founder, Adam Miller, met Joe Stanish of CSS Composites back in 2010 when Stanish was still VP of Operations at ENVE, but it wasn't until last year that things came together. In 2019, Joe approached Revel with the idea of utilizing a new material that was being developed at CSS Composites that he claimed was stronger, lighter, more cost-effective, could be made in America, and is 100% recyclable. Stanish wanted to partner with Revel to introduce the first bicycle rims made of this material, and Fusion-Fiber was born.
Revel RW30 Details
• Intended use: All-mountain / enduro
• Double-wall Fusion Fiber rim
• 28 hole, 3-cross lacing
• 35mm external, 29mm internal width
• Hub: Industry Nine Hydra, 690 P.O.E.
• Weight: 1,840-grams (29") / 1,730-grams (27.5")
• Rims available individually, 28/32h ($700)
• Laid up and molded in Gunnison, Utah, USA
• Lifetime warranty
• Price: $2,200 USD / $700 rim only
On the surface, the rims don't look all that different than any others out there. They're made with the same material as a traditional thermoset carbon rim, but a second glance shows that the material is quite different: The epoxy used in a thermoset rim is absent, and the binding agent in its place is an advanced polymer; picture nylon holding the strands of carbon together.
The rims are available as a wheelset with either Industry Nine's 101 or Hydra hubs in both 27.5" and 29" versions, and also as a rim-only in 28 or 32 hole drilling patterns. The wheels I'm testing are the 29" version on Industry Nine's Hydra hubs, weigh 1,840-grams on my scale, and sell for $2,200 USD. Going with the 101 hubs will lose you a little bit of engagement and $300 from the price, or you can pick up a bare rim for $700. Thermoset vs Thermoplastic
Before we discuss the rims themselves, let's look at the basic differences in thermoset and thermoplastic materials. Put simply, both utilize the same fibers but a very different glue.
Thermoset materials include nearly everything you can think of that we traditionally call carbon fiber. That goes for frames, rims, and other components. The process for making a thermoset product involves taking sheets of carbon fiber which, in this case, are held together with a two-stage epoxy that acts as the matrix (AKA glue). The fibers are laid down into the mold, epoxy is added to the equation, and then it's cooked. Once cured, the carbon is set and cannot be changed, which is where the name "thermoset" comes from. Thermoset carbon has a finite shelf life and must be kept at certain temperatures, usually in a refrigerator, before use in laying up a product and adding the epoxy.
Thermoplastics also use strands of carbon, but the way that they're laid up is different. The fibers start similar to a thermoset carbon, as a raw unidirectional tape, but are then turned into a thermoplastic by using a polymer to act as the matrix (glue) and hold things together. There are also various advanced polymer recipes that can be used depending on the application. The polymer-based glue can be melted back down into a liquid state and formed or recycled into other products as many times as desired. Thermoplastics are typically less brittle, more ductile, and more flexible than epoxies. There are countless uses outside of bike products; for instance, airplanes utilize thermoplastics in various components. Thermoplastic carbon is stable and has an infinite shelf life, and it doesn't need to be refrigerated before final construction to maintain its integrity.
Anything that is currently made of traditional thermoset carbon fiber could be made with a thermoplastic, but the cost and availability of equipment to produce products have been the biggest limiting factor.Fusion-Fiber Rims
Fusion-Fiber is a product used by Revel for their rims, much like how Gore-Tex is used and licensed by many different companies to make various products. Revel's Fusion-Fiber thermoplastic rims are constructed in a very similar fashion to a traditional thermoset rim as far as laying up carbon goes. There are fibers laid out in various directions that are then stamped into a bias-ply sheet, similar to how you would stamp and form metal. The difference is that Revel is using a robot instead of laying things up by hand, thereby removing the variability of human error. The machine can also put down one layer per second.
The materials are then fused together with Fusion-Fiber, whereas traditional thermoset components are epoxied and cured. This means that there is no material waste or burn-off in the process, and unused fibers can be chopped up and remolded. There are also no added chemicals. The Fusion-Fiber layers are flash-welded together with electricity, a process that takes between twenty and sixty seconds.
The process of using the Fusion-Fiber sheets for manufacturing the rim is something Revel isn't keen on sharing with the world, but the basic (and over-simplified) process involves pieces of thermoplastic put into the mold and flash-welded into a rim. The rim then goes through three different heating and cooling steps, and requires no sanding, clear coat, or paint when it pops out of the mold. Recyclability
One of the notable drawbacks to traditional thermoset carbon fiber is excess or damaged products are difficult to recycle - when a thermoset frame or rim reaches the end of its life cycle, it's typically trash. While it can be done in some cases, it's said to be not as cost-effective as starting from scratch, which leads to a lot of waste. There are also hazardous byproducts produced in the manufacturing process.
Being a thermoplastic, Fusion-Fiber is claimed to be easily recycled. CSS, the company that makes Fusion-Fiber, can recycle it themselves by chopping it up into smaller pieces and melting it down to form parts that use short fibers, like stems and other small components. Everything is said to be easily and infinitely re-moldable into something else, whether it's in the bike industry or elsewhere.
Joe Stanish, COO of CSS claims they have full control over the recycling process of the material. They say this allows them to know exactly what they're getting, and that it's of much higher quality than mass-recycled plastics that can have all sorts of variances in them.RW30 Wheels
My test wheels are the RW30s, the only model that's currently offered, but Revel will have different options in the future.
Thermoplastics are claimed to offer some differences in ride quality that can be seen as advantages. The material handles impacts somewhat differently by giving what Revel and CSS claim to be over 50% more vertical deflection in impacts without sacrificing any lateral stiffness. If true, they should offer a stiff but not harsh ride quality. With a thermoset rim, it's difficult to design the wheel in a way that allows more vertical compliance without sacrificing lateral stability - it's inherent in the way the epoxies harden.
According to Revel, the polymer in the thermoplastic flexes in a smaller region for a given impact, whereas almost a third of the wheel flexes with a thermoset rim for the same impact. That's said to help with the stability while also offering that vertical compliance, as well as being quiet and durable in the case of rock strikes.
Revel and CSS didn't stray too far from convention with the RW30 wheels, going with a standard double-wall design rim that they say offers an excellent ride quality when paired with the Fusion-Fiber. The internal rim width of the RW30 is 29mm and aimed at aggressive trail and enduro riding.
All of the rims are covered by a lifetime warranty that includes Revel paying for shipping and handling should anything happen. It also covers getting a loaner set while your new wheels are built up and the old rims are recycled.
The rims use a traditional double-wall design but coming out of the mold, there is little work to be done as they don't need paint, clearcoat, or anything else.First Impressions
I've only had the RW30 wheels out on a couple of short rides at this point. Mounting up tires was straight forward, and I had zero issues airing up with a standard floor pump. In my time on the trail, I can confirm that they deliver in terms of stiffness and compliance, and I've had zero issues with anything otherwise. The wheels do seem to do a good job of damping trail chatter, especially at high speeds, and there is something unique about the way they ride compared to other carbon wheels that I've been on.
Long-term use is yet to be seen, but we'll provide an update once I put a lot more miles on them.