We have been looking forward to getting our hands on a set of these ‘entry level’ aero performance wheels for a while.
They are the base model for time trial and triathlon use, and are also part of Bontrager’s road race line up. ‘Entry level’ is perhaps a slightly misleading phrase for a £900 wheelset. The price point, claims for aero efficiency, and intent of the Aura 5 brackets them with Mavic’s Cosmic Carbone SL.
That said, the price point is significantly lower than wheels with rims of a similar depth from Reynolds, Fast Forward and Zipp. Available solely in clincher format, and not tubeless compatible out of the box, the Aura 5 clearly carries the confidence of Bontrager’s engineers, who have placed no rider weight restriction on the wheels.
So what do you get for your £900? A 735 gram and 995 gram, front and rear wheel set (Bontrager’s claimed weights for either were pretty darned accurate). They’re formed from an aluminum rim and main body, with a super light, unidirectional carbon aero shroud that forms a blade with which to slice through the air. The carbon is extremely thin and visibly flexes when you push and prod it. Like many modern rims, the Aura has a 23mm wide profile, allowing a 23mm tyre to sit flush with the rim, improving the aero efficiency of the combination.
The depth of the entire set up is 50mm. The rim profile is not quite as curvaceous as the Zipp Firecrest, or as blade sharp as the aforementioned Mavic. The b-spline curve of the Aura 5 has been honed in a wind tunnel to optimise its performance in a multitude of wind directions, Bontrager claim, and based on knowledge gained from their upscale Aeolus range.
At the front are 18 radially-laced DT Swiss Aerolite spokes attaching the rim with alloy nipples and laced to an alloy hub. The rear has a two-cross pattern in both drive and non-drive sides. With only three pawls in the freehub, we’re expecting a slower pick up than that offered by, say, Chris King, but we’ll reserve judgment until fully tested. Alloy nipples are used to hold the spokes onto the rim, so we are going to give them some abuse this winter.
The Bontrager Auras are supplied with quick releases and valve extenders. We are looking forward to getting out on the road with the test set and trying them out.