The Fulcrum Racing Light XLR clincher wheelset has a lightweight, carbon box-section rim, a tall asking price and many competitors that are better aerodynamically. At BikeRadar, we’re left wondering whether the market still needs box-section race rims.
At 1,413g a pair (1,450g including rim tape), the Racing Light XLR is promoted as "the ultimate climber's wheel". Rim weight is kept low to reduce rotating mass, although this isn't a significant force acting against a rider. Acceleration efforts were rewarded with little resistance and the wheels quickly gained speed. Their speciality is climbs, though, and as the road headed toward the sky the Racing Lights excelled.
With 22 spokes front and 24 rear, the Racing Lights have just the right balance of stiffness and low weight. Out-of-the-saddle sprints and high-gear efforts gave no hint of wheel flex, our efforts rewarded with nothing but forward momentum.
So far, so good, but bear in mind that the Racing Light XLR set is less than 50g lighter than Fulcrum’s brilliant aluminium Racing Zero, which is less than half the price of the XLR and has improved braking performance to boot (more on that below). Also, on rolling flats it was harder to hold speed than with deeper race wheels, and that left us wanting more carry-over momentum.
A large driveside hub flange and Fulcrum's 2:1 spoke lacing pattern aid stiffness
Rim widths on the Racing Lights veer away from the current trend towards wider being better. Due to the think carbon layup, the 12.79mm internal measurement translates to a 20.27mm outer rim width. We didn’t see this as a negative, though, as they proved comfortable thanks to a low rim profile and stainless steel spokes.
Over imperfect roads, the Racing Lights go a long way to deadening the surface. Even on larger hits, such as potholes, both the physical impact and sound were reduced to a comfortable level.
The carbon-shelled hubs are well sealed, and externally adjustable with standard tools. They roll effortlessly, with unquestionable smoothness due to the fitted greaseless ‘CULT’ ceramic bearings, top in Fulcrum’s range and claiming nine times greater smoothness than standard stainless steel bearings.
Fulcrum have a great reputation for their hubs. Not surprising considering their sister company is Campagnolo
The Achilles’ heel of many carbon rims is their ability to stop. On the Racing Light XLRs, Fulcrum have done a great job of creating a consistent brake track with no hint of pulsing, grabbing or squealing, providing a well-rounded, reliable braking surface. But because these wheels are comparable to some aluminium options, it’s worth noting that a good aluminium rim still provides greater brake feedback, stopping power and durability.
Thumbs up for build quality
Out of the box, the Racing Light XLRs were perfectly true, and built with high spoke tension. The wheels include a warranty card that’s traceable back to the original builder, helping to ensure that quality control remains a top priority for the Italian company.
We continue to love the action of the Fulcrum internal cam quick-release skewers, even with their hefty 118g weight. In addition to the skewers, the wheels include a pair of branded wheel bags, non-scratch tyre levers and Fulcrum's own carbon-specific brake pads.
With so many weight competitive aero options available, though, the Racing Lights are a hard ask. If it were us spending the money on a pair of race wheels, we’d go for one of the faster options out there.
Note: The Fulcrum Racing Light XLR wheelset is also available in Australia, through FRF Sports, for AUD$3,780.