On Thursday, Bontrager announced the Aeolus Pro V wheels, for road or gravel riding. The new wheelset features new thermoplastic construction and comes in two different depths, 37 mm and and 49 mm, with the former suitable for general gravel riding and racing, and the latter for running high-volume road tires or gravel racing, when aerodynamics becomes a more important factor.
Thermoplastic carbon construction: a greener way
The Aeolus Pro V wheels use thermoplastic carbon construction. This is slightly different from traditional carbon fiber construction most commonly in used for wheels, bars and bikes. In simplify terms, both carbon fiber and thermoplastic carbon uses sheets that are placed in molds, with the addition of a bonding agent, under heat and compression, are formed to make the structure of whatever you are creating, whether it be a wheel, frame or other components.
Benefits of thermoplastic
Both composites use similar materials, but the difference is the “glue” that bonds them. Carbon fiber uses thermoset resin, or epoxy, and the latter uses thermoplastic, or polymer. There are two byproducts in this process, the most notable being the ability to re-use thermoplastic carbon. Once traditional carbon fiber is cured, it is set, the chemical change means you cannot further modify the form it’s taken.
With thermoplastics, the compound used means the finished product can still be melted and remolded. This method is becoming more popular in the cycling industry as it means you can use leftover scraps, broken materials or older frames and parts and use them for something else.
The rim is produced using a laser-machined mold, which means there is no need to sand it when it’s complete. But it’s not just about looking slick–it also trims some weight and doesn’t need any more paint or decals. More importantly, Bontrager says the process results in a reduction of up to 95 per cent in volatile organic compound (VOC) and carbon dust emissions that conventional carbon rim finishing methods utilizes.
The result, Bontrager says, is a stronger, smoother–and greener wheelset. Not only is the building process better for the environment, the properties of thermoplastic create a less harsh response on the road. With slightly more give than traditional carbon, the Aeolus Pro V wheels absorb vibrations by dampening the bumps in the road.
Wide and aero rim
Both Aelous Pro V wheelsets come in 25 mm inner widths and the rim is disc-only. Bontrager recommends going no lower than a 28 mm tire on the wheels, as they have been fine-tuned to accommodate higher volume road and more specifically, gravel tires.
The Aelous Pro V wheels are Tubeless Ready (TLR), and come with Rapid Drive 108 road hubs, compatible with Shimano 10/11/12 and SRAM 10/11 freehubs.
Lightweight and reliable
The wide rims allow you to maintain lower tire pressures for enhanced traction and a swifter, more assured riding experience. The 37 mm hoops weigh in at 650 g for the front and 815 for the rear, and the 49 mm version is 690 g and 865 g.
With the wider rim, it allows you to maintain lower tire pressures for enhanced traction and a swifter, more assured riding experience.
Carbon Care protection
Bontrager carbon wheels carry a lifetime warranty for the original buyer, coupled with the extra safeguard of Carbon Care. If you encounter structural damage to your wheels during the initial two years of ownership while riding, Bontrager will provide a replacement.
First ride impressions
The wheels are set for tubeless right out of the box which saves a lot of time and hassle. For the test, we mounted a set of Bontrager GR2 40C tires which were surprisingly easy to install. We didn’t even need a tire lever or a long break between wheels to regain hand strength. There is also a noticeably different hand feel to the rims. The rims don’t feel ultra smooth like a lot of carbon wheels but have a slightly more plastic feel which seems less brittle and more resilient.
On the road
Out on the road the wheels spin up to speed quickly as would be expected from a wheel with its weight. At 37 mm deep the Aeolus provides enough of an aero advantage to notice over shallower profile hoops however they are not so deep that a strong gust of cross wind will put you in the ditch. Bontrager has really hit the sweet spot with rim depth on these for gravel use.
The effect of thermoplastic on the road
One of the advantages Bontrager boasts about the thermoplastic construction is its ability to dampen vibration. We were skeptical that there could be much of a difference over traditional carbon construction but the Aeolus wheels did seem a little smoother over our rough gravel test track. We also found that thanks to the slightly smoother ride it was a little easier to hold and find your line when things get bumpy. The ride quality is exceptional, but potentially comes at a slight cost, because when you stand up out of the saddle on road sections to put the power down they don’t feel quite as stiff and responsive as comparable Bontrager road-specific wheels.
With only a few rides on these so far we can’t speak to the long-term durability yet, but they have held up to some pretty good washboard gravel roads and the occasional pothole hit without any issues. But I am definitely looking forward to more road and gravel rides on these to really test their limits.
Aeolus Pro 37 V or 49 V front wheel $1,200
Aeolus Pro 37 V or 49 V rear wheel, $1,280
Available at TrekBikes.com