The new FSA Metron 45 and 60 SL wheelsets get updated aerodynamic rim profiles optimized for 28mm tires, plus new PRS helical ratchet hubs that are not only lighter, but way faster to engage. But that’s not the only benefit to the new design…
Coming in tubular and tubeless clincher options, we covered all of the options and specs when they debuted at the Tour de France this summer. Check that post for rim profiles and all of the options. Here, we’re taking a closer look at the new hubs with a couple of fresh videos from FSA and our own cutaway photos…
Both the 45 SL (45mm deep) and 60 SL (60mm deep) do more than just go wider (21mm internal, up from 19mm), they’re both 5mm deeper than the wheels they’re replacing. The new shape and depth give them small drag savings with both 25mm and 28mm tires, ranging from 4.2W up to 5.5W depending on the pairing. They’re also a lot more stable in crosswinds.
Despite the deeper profiles, the rims get a lighter layup, with reinforcements at the spoke holes. It’s not just the layup itself, but FSA says they’re hand laying them with a more refined process to create a lighter overall rim that’s still World Tour tough.
New Vision PRS hubs
The new PRS hubs are lighter than ever, thanks to all-new internals, a stiff forged alloy shell, and tool-free end caps. Claimed weight for the rear hub is just 218g, and that’s with four sealed cartridge bearings inside. The front hub remains fairly standard with two sealed cartridge bearings.