Gravel Wheel Test: Derby CX23i

Built to last and made to order

Derby’s unique spin on wheels

Derby is the product of an old-school mountain biker with innovative thinking and the drive to make high-performance carbon rims for the masses. Ray Scruggs was never in the hunt for leaders’ jerseys or finish podiums. He’s just a regular guy with a long history of computer programing and analysis with a high level of attention to detail. 

In 2012 he set out to design carbon mountain bike rims that were both affordable and durable while also providing real-world performance gains. This all sounds great, but we ride road bikes and, luckily, so do some of Ray’s friends, so along with his line of mountain bike hoops are a few drop-bar-optimized options.

THE TECH

The 33mm-deep CX 23i is a hookless bead rim that uses a parabolic rim shape with 29mm external and 23mm-wide internal widths. The internal rim channel is slightly deeper than normal, making them very easy to mount tires. The internal-rim profile also has a slightly higher bead-retention ridge, which locks the tire bead into position against the hookless bead.

The rims are designed to only be paired with tubeless tires. Derby offers the CX 23i in 24-, 28- and 32-hole count so you can have them laced to nearly any hub. For our build, we opted for the equally impressive Onyx Vesper CL hubs. The American-made Onyx hubs are best known for having silent, low-drag and instant engagement, thanks to their sprag-clutch engagement. The alloy hubs use ceramic bearings on top of interchangeable steel and alloy hub bodies. Did we mention that they also can be ordered in nearly any color your heart desires?

For our build, we opted for 24 spokes up front with 28 spokes in the rear. To match the orange hubs, we also got orange alloy nipples for a splash of coordinating color. The build is a balance of flair and performance, with durability remaining the top priority. 

THE RIDE

Derby recommends a tubeless tape only in the deep-center channel to produce the best tubeless seal when the tire is seated. This allows the tape to cover and seal the spoke holes while letting sealant better bond to the carbon around the tire bead. This, in the end, worked out, but we did have to re-tape, because the original tape was leaking sealant into the rim cavity through one of the spoke holes. With this system, the edge of the tape is not being held down by the tire, so it is very important that it is installed correctly.

While in the end they sealed up and were problem-free, the first attempts were less than ideal, as the tires would slowly deflate over 20–30 minutes. Another solution would be to run a wider bead-to-bead tape like most other brands, but Derby does believe when done correctly, their technique offers the best long-term performance. 

For the test, we ran everything from 45mm Kenda gravel tires all the way down to 25mm road tubeless tires and plenty of sizes in between. All the tires beaded up easily and, just as promised, stayed locked onto the hookless bead even when we completely deflated the tires. In fact, it was harder to get the tires off the bead than it was to get them on, and that’s a good thing.

“As the market is flooded with featherweight race-wheel options, it’s nice to see wheels that are targeting riders who don’t want to spend as much time repairing wheels as they do riding them.”

As expected, the 23mm-wide rim profile does boost all the labeled tire sizes, but even with the biggest gravel tires we tested, the tire sits with a very supported sidewall. This made for more predictable cornering, as the tire wouldn’t roll at low pressures. The wheels are stiff laterally and vertically. The rim shape and thick hookless bead made rim strikes worry-free. Sure, the impacts are audibly unsettling, and we wouldn’t recommend running pressures so low that rim strikes are normal, but the durability of these hoops was impressive. 

Simply put, the Onyx hubs are unlike any other on the market owing to their instant engagement, which was most appreciated when things are rough and power is in demand. The silence is also a bit refreshing since many hubs on the market are getting louder as more points of engagement are added and wheels get deeper. The real downside to the rear hub is its weight, and that’s reflected in the 978-gram rear wheel. Luckily, that is at the center of the rotating mass and really isn’t felt during riding. The front hub is lighter, but doesn’t make up for the added
rear mass.

THE VERDICT

Overall, the wheels aren’t winning any diet competitions, but for a gravel or adventure bike, that’s probably more acceptable. The added weight is a trade-off for durability and excellent hub performance. The internal rim width is probably best paired with 30mm tires and larger, but we were happy with the way even the 25mm tires performed. We found that 38mm-and-bigger tires and the style of riding they are normally associated with are where these wheels really performed. 

The rim’s parabolic shape is incredibly strong, stiff and responsive. These wheels would be a capable mountain bike wheel in most brands’ catalogs and would probably have a trail/all-mountain recommendation. What does this mean for the drop-bar category that Derby recommends them for? Years of abuse, neglect, adventure and, most important, worry-free fun.

As the market is flooded with featherweight race-wheel options, it’s nice to see wheels that are targeting riders who don’t want to spend as much time repairing wheels as they do riding them. The Derby rims look to offer a problem-free riding experience. 

The recommended setup is a bit different when it comes to internal rim tape, but the theory seems valid. For us, the Onyx hubs are a gem and really elevated the entire experience. No matter which hubs you choose, the Derby hoops seem to be built to handle all that we could dish out on our drop-bar bikes.

PUNCH LINES

Wide and hookless done right

Proper setup is key

Custom builds are the only way

STATS

Price: $1966, wheelset; $495, rim only

Weight: 743/978 (1721) grams

www.derbyrims.com

www.onyxrp.com

carbonGravelwheelsDerbyCx23iOnyx Hubs