Bontrager Aeolus RSL 51 TLR on test

All-round wheels with 50 mm rims? That’s right, the Bontrager Aeolus 51 TLR set out to achieve the impossible. Trek’s in-house brand offer aero wheels that claim to set the standard with a classic and classy look. How do they stack up against the competition? We put them to the test to find out.

**Bontrager** Aeolus RSL 51 TLR | € 2,599.98 | 1425 g | Manufacturer’s website

We tested these wheels for our big 2024 aero wheel group test – click here for an overview of the test field or to check out the individual reviews.

Besides having a name that nobody really knows how to pronounce, Trek’s marketing of the Aeolus RSL 51 is as modest as always ;). They’re not just claimed to be the fastest of all time, but also offer ultimate speed, maximum stability, and maximum confidence in all conditions. As such, the wheels promise to excel in every situation – and that seems to hold true for the pros of team Lidl Trek. But do they have what it takes to beat the competition in our test field? With DT Swiss hubs, and a special tubeless setup, the specs seem to point in the right direction, though the V-shaped rim geometry looks a bit dated at first glance.

The specs of the Bontrager Aeolus RSL 51 TLR

At € 2,599 per set, the Bontrager Aeolus RSL 51 are priced slightly below the test field average, which is unusual for Trek, whose products are regularly at the upper end of the price range in our tests. The weight, on the other hand, is more typical for Trek – slightly above average at 1,425 grams (excl. the freehub). Nonetheless, the weight is still quite impressive for a wheelset with 50 mm rims. By using classic spokes with a minimal aero profile, Trek dispense with the higher weight and aero gains of carbon spokes. The hubs look rather unspectacular too, but that doesn’t necessarily mean anything. Bontrager rely on what is probably the most proven brand in the wheel industry: DT Swiss’ 180 hubs aren’t just modern, but also highly reliable, easy to service, and backed by an extensive dealer network.

**Minimal aero**
Bontrager rely on bladed spokes for the Aeolus RSL 51, though they look rather conservative compared to some of the big, flat carbon blades on test.

**DT Wisconsin?**
Bontrager rely on proven hubs from DT Swiss paired with the Swiss brand’s latest spokes

**Shiny!**
The glossy finish of the rims is unique in the test field and gives them a high-quality look

The rims, on the other hand, are supplied entirely by Trek. With an internal width of 24 mm, external rim width of 31 mm, and a measured depth of 52 mm, at least the key specs match the current trend towards wider rims. However, Trek seems to be taking a different approach with the rim shape. In contrast to most aero rims, the Bontrager Aeolus RSL 51 are less bulbous, with a shame more reminiscent of the tapered models from previous years. However, Bontrager have come up with a smart solution to the tubeless question. Thanks to their TLR rim strip, a white plastic insert similar to rim tape, the rim can be sealed in no time and promises long-lasting, puncture-free tubeless fun. Overall, the wheels are a visual treat, with the high-gloss rims and black decals as well as the elegant DT Swiss hub resulting in an incredibly high-quality and classy look.

**Tubeless made easy**
Thanks to Bontrager’s in-house design with a plastic tubeless strip, there’s no need for rim tape

**Reinvented**
The pointed rim profile is reminiscent of the first aero wheels. However, Bontragers have managed to bring the design up to date with current performance standards.

Bontrager are rather generous with their warranty too: in addition to a lifetime warranty for the original owner, they also offer a two-year loyalty program. If the wheels break during this period, Bontrager will replace or repair them free of charge.

Bontrager Aeolus RSL 51 – All-round feel on a race wheelset

As Bontrager proclaim, the Aeolus RSL 51 shouldn’t just deliver in terms of aerodynamics, but also set the standard when it comes to handling. As our tests can confirm, the extremely composed and predictable handling is complemented by a perfect level of compliance. The wheels aren’t just fun on smooth, brand-new asphalt, they also fare well on old and poorly maintained roads. Nevertheless, there’s no denying their performance oriented character. The Aeolus never feel too flexy or vague, always providing ample feedback from the road. Due to the stiffness, especially of the front wheel, the steering feels precise, allowing you to hold your line perfectly through the corners.
Although the Bontrager Aeolus RSL 51 are fast and responsive, you’ll notice their slightly higher weight on the climbs, especially when accelerating out of tight bends, which is further confirmed in crosswinds. Compared to the competition with the same rim depth but wide carbon spokes, they remain stable even in heavy winds, proving to be true all-rounders.

Bontrager Aeolus RSL 51 – Made for speed

An all-rounder with high aero performance? We had our doubts about that, at least as far as the rim shape is concerned – in fact their performance isn’t on par with the test field average. The direct competition from CADEX and HUNT feels faster and gets a significant boost from the sail effect. The results from the wind tunnel confirm this impression. However, their performance at low yaw angles up to about 5° is surprising. In this case, the Bontrager Aeolus RSL 51 even partially beats our group test winner, the Syncros Capital SL Aero. But above that, their performance drops off rapidly, especially at the crucial average yaw angles of 10°. On average, the Bontrager Aeolus RSL 51 lands in 5th place, about 2 watts behind the test winner, and just 1.5 watts ahead of the competition from CADEX and HUNT. However, this result is heavily skewed by their excellent performance at low yaw angles.

Our conclusion on the Bontrager Aeolus RSL 51

Bontrager’s Aeolus RSL 51 is an excellent all-round wheelset. Their compliance and ride feel offer a perfect compromise for everything from long training sessions to racing. It’s a great choice for those who want an all-round performance wheelset thanks to their responsive acceleration and stable handling. It performs surprisingly well in the wind tunnel too. Due to the somewhat old-school rim geometry, however, it performs best at shallow yaw angles.

Tops

classy look with glossy rims
DT Swiss hubs with ceramic bearings
outstanding performance in the wind tunnel for 50 mm deep rims

Flops

somewhat dated rim geometry

For more information, visit trekbikes.com

The test field