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by Matt Wikstrom
March 17, 2015
Photography by Matt Wikstrom
Curve is a small wheel brand that is based in Melbourne, Australia. The company started as a collaboration between a couple of riding mates and offers a range of high performance wheelsets for road, off-road, and cyclocross riders. In this review, CTech editor Matt Wikstrom takes a look at Curve’s 38mm carbon clincher wheelset.
Curve Cycling was born out of the enthusiasm of two BMX buddies, Jesse Carlsson and Steve Varga. They grew up in South Australia, racing and jumping, before Jesse gave up bikes to pursue a PhD in Melbourne. Steve also moved to Melbourne, picked up some work in a bike shop and discovered a love for mountain biking before coaxing Jesse back on to the bike.
Around 2007, Steve became interested in product development, and in particular, wheels. Not content with marketing hyperbole, he set about learning what Asian manufacturing had to offer. After a few years of experimentation, Steve found a reliable source of carbon rims and with the help of Jesse (who had founded his own capital investment firm), Curve Cycling was born.
Adam Lana was one of Steve’s early customers; he also has a background in marketing and branding. He joined Curve in 2013 to take care of developing the brand, leaving Steve free to concentrate on products. Jesse is normally called upon to test the wheels that Steve builds, where his interest in ultra-marathon cycling serves him well. Indeed, Curve was launched with his attempt at the Tour Divide in 2013, the world’s longest unsupported MTB race, where Jesse finished in second place.
Curve’s product development and promotion is helped further by an extended family of riders in various disciplines. The company’s current catalogue and online shop is stocked with performance-oriented wheels for road, cyclocross and off-road use. All of the wheels use carbon rims in both stock and custom configurations, though Curve is starting to look at alloy rims and framesets too.
Curve’s current road range offers three carbon clincher rim profiles—24mm, 38mm and 50mm—that are tubeless compatible with a retail price of $2,179-$2,229 for a stock build. For this review, I spent a few weeks riding a set of Curve’s stock 38mm carbon clinchers.
Curve’s 38mm carbon rim is (unsurprisingly) 38mm tall and 23mm wide with a toroidal profile that is well known for its aerodynamic properties. As mentioned already, the rim is tubeless compatible, and uses a brake track designed for high temperatures.
Curve’s stock build utilises a DT 240s hubset with 20 holes for the front and 24 holes for the rear. For those that are unfamiliar with DT 240s hubs, they have a reputation as a robust hubset, plus there is the appeal of tool-free servicing and a unique ratchet drive.
All of Curve’s stock wheels are laced with Sapim CX-Ray spokes and alloy nipples. These semi-bladed spokes have a sound reputation, offering enormous tensile strength at a low weight. Radial lacing is used for the front wheel compared to two-cross for both sides of the rear wheel.
Curve offers a sturdier 38mm carbon clincher rim that measures 25mm in width and adds around 90 grams, which should suit heavier riders or light off-road/cyclocross use. Curve’s other custom options include White Industries T-11 hubs, Tune hubs, tubular rims, custom decals, and the freedom to supply your own hubs.
It is worth noting that Curve recently gained UCI-approval for its 50mm rims and now they’re working on getting the same approval for their 38mm rims. For most buyers, it’s an unnecessary step but the guys at Curve are keen to ensure that their racing wheels can be used at the highest levels of competition.
The wheelset sent for review weighed 1,482g (677g front, 805g rear) with rim tape but without skewers. Recommended retail is $2,199 and buyers have a choice of Shimano/SRAM or Campagnolo freehub bodies. Titanium skewers and carbon-specific brakepads are included.
Curve is open about the shortcomings of carbon clincher rims. The company offers a two-year warranty on its wheelsets. In addition, they offer a 25% discount for crash replacement and 50% discount to replace heat-damaged rims. For more information, visit Curve Cycling.
The strength of any mid-profile rim is that it promises a little bit of everything without an excess of anything. Curve’s 38mm wheelset delivers on this promise with a versatile rim profile that largely ignores the wind, a low weight that enhances acceleration, and plenty of stiffness for race-day efforts.
While the rims were stiff, I never found them uncomfortable. I noticed a little extra road buzz when switching to these wheels from my regular alloy clinchers (Stan’s Alpha 340), but it never overwhelmed me (or my hands). The stiffness was most noticeable when bunny-hopping kerbs and other road debris because the landings were harsher.
The stiffness of the rims really shone every time I got out of the saddle to accelerate the bike. The low weight of the rims helped the responsiveness too. Both aspects make for a potent combination that is perfectly suited to (and promotes) a race-day riding mentality.
For some riders, all of that race-tuned stiffness may be too much for all-day and/or everyday riding. I spent the entire review period on 23mm tyres, so I can’t report on how much difference a set of 25mm tyres would make, but based on my experience with other wheelsets, I’d expect a noticeably smoother ride.
I can’t comment on the aerodynamics of the toroidal shape, and there isn’t any data that promises a tangible time gain over a set distance. This is the realm where marketing hyperbole typically dominates but the boys at Curve like these rims for their width and the fact that crosswinds have trouble catching the front wheel, and I agree with them.
I found braking on the 38mm rims was very good and inspired plenty of confidence, at least in the dry. As mentioned above, Curve is open about the susceptibility of carbon rims to heat damage, and while they insist on the use of carbon-specific brake pads, there are no limitations on the brands that can be used. I’d personally recommend Swissstop’s Black Prince pads.
I took advantage of the tubeless compatibility of the rims to compare the tubeless and standard clincher versions of Schwalbe’s One tyres. Both formats were easily installed on Curve’s 38mm rims (no need for tyre levers) and I didn’t have any trouble inflating and sealing the tubeless tyres.
Out on the road, the standard tyres were suppler than the tubeless version, providing better road feel and a sense of performance. Indeed, the tubeless tyres felt dead by comparison, which I presume can be attributed to the extra rubber required to render the casing airtight. I expect most riders will find the standard clincher is a better match for this race-oriented wheelset.
A wheelset is comprised of four basic elements—rims, hubs, spokes and nipples—that can be manipulated to meet a wide spectrum of needs. By pairing high-end hubs and spokes with stiff and light rims, Curve has created a wheelset that offers a fine race-tuned performance. Riders that enjoy all-day rides may find it a little too stiff, while climbers are likely to prefer something lighter.
Curve’s stock wheelsets offer buyers the convenience of a factory-built product that has the feel and specifications of a boutique custom build. At the same time, they are equipped to customise their wheels according to the needs of their customers.
Curve could have improved its profit margin and satisfied consumer demand for a lower-priced carbon wheelset by using cheaper hubs and spokes but they didn’t meet Steve’s standards or survive Jesse’s testing. Curve may not have the reputation of a big brand but their diligence is more than enough compensation.