Giro riders spotted using new CeramicSpeed aero derailleur fairing

The Wilier Turbine SLR
(Image credit: Wilier)

Just moments after we reported on the launch of a new Wilier Turbine SLR time trial bike complete with an aerodynamic fairing attached to the rear derailleur, riders at the Giro d'Italia were spotted using a similar-looking component. 

Spotted on the Factor Ostro VAM of Giacomo Nizzolo (Israel-Premier Tech) , the derailleur cage appears to be solid in construction, similar in design to the SLF Motion Evo Aero. However, after a little bit of digging, Cyclingnews understands the component to actually be an unreleased aerodynamic Oversized Pulley Wheel from marginal gains specialists CeramicSpeed. The retail price for the component, according to reports by Triathlete, will be $800.

According to that same report, the system was developed as a collaboration between CeramicSpeed and British aerodynamics consultants Drag2Zero, a company founded by Simon Smart, whose aerodynamics expertise spans both cycling and Formula One.

At the moment, we have no details of the construction of the product, but from the images available, it appears to be a complete pulley wheel system similar to CeramicSpeed's existing OSPW or AbsoluteBlack's Hollowcage. However, the clear difference is how the device is shrouded in an aerodynamic carbon fibre fairing, with a rounded leading edge and an open rear. 

It is black in colour, but made easily identifiable thanks to the white spikes travelling rearward through the product, mimicking the direction of the wind. 

Those well-versed in the UCI’s equipment regulations may query its compliance with Article 1.3.024: “Any device, added or blended into the structure, that is destined to decrease, or which has the effect of decreasing, resistance to air penetration or artificially to accelerate propulsion, such as a protective screen, fuselage form fairing or the like, shall be prohibited.”

In the absence of any official confirmation from CeramicSpeed or Israel-Premier Tech, we reached out to the UCI for clarity. 

"The UCI is aware of the product and has been in dialogue with the manufacturer," explained the UCI's Head of Road and Innovation, Michael Rogers. "The product is considered as a derailleur cage and hence a structural part of the rear derailleur."

Rogers also went on to clarify the UCI's rules around commercial availability. "Concerning commercial availability requirements, the product complies with article 1.3.006 of the UCI Regulations". 

While this looks to be a novel idea in the pursuit of marginal gains, it's not the first time a rider has used an enclosed derailleur cage. Both Fabian Cancellara and Lance Armstrong have been seen to use a similar device from German company Berner. It's also not the first of its kind to hit the market; the aforementioned SLF Motion is just one company touting aero cages as the latest marginal gain for cyclists and triathletes.

Given the absence of official details about the product, we are also without any information on the aerodynamic benefit afforded to its users. The existing CeramicSpeed OSPW claims a saving of two to four watts from reduced drivetrain friction, so we expect similarly small additional savings from this aero system. But marginal gains are just that; marginal, and every watt adds up. 

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Josh Croxton
Tech Editor

As the Tech Editor here at Cyclingnews, Josh leads on content relating to all-things tech, including bikes, kit and components in order to cover product launches and curate our world-class buying guides, reviews and deals. Alongside this, his love for WorldTour racing and eagle eyes mean he's often breaking tech stories from the pro peloton too. 


On the bike, 30-year-old Josh has been riding and racing since his early teens. He started out racing cross country when 26-inch wheels and triple chainsets were still mainstream, but he found favour in road racing in his early 20s and has never looked back. He's always training for the next big event and is keen to get his hands on the newest tech to help. He enjoys a good long ride on road or gravel, but he's most alive when he's elbow-to-elbow in a local criterium.