The advantages of deep, carbon rims are evident to anyone who has ever held 20-25 mph on flat, straight roads for an extended period. The disadvantages are equally evident, and they usually manifest as unresponsive, obnoxiously-loud braking or equally poor and obnoxious handling when a sudden crosswind throws you across the road. HED's Jet 4 Plus Black wheels remedy both issues with rim shaping and the newly improved Black braking track.
The most striking feature setting the Jet Black models apart from the regular Jets is the black finish of the brake track, which is the result of HED's Turbine Braking Technology. HED claims this design nets some pretty impressive numbers, including stopping distances in dry and wet conditions that are reduced by 25% and 70%, respectively, and brake power consistency that enjoys a claimed 5x increase.
It's also important to keep in mind that, since the Jets use an aluminum brake track, these are increases over the exceptional braking of alloy rims, not the poor braking of carbon, so the Jet Black models easily enjoy the most consistent stopping power of any aerodynamic wheels in the industry. This better-than-alloy brake track is also, obviously, black. We unashamedly admit that this appeals because it doesn't interrupt the otherwise stealth look of the 46mm carbon rims with a bright, silver brake strip.
HED claims that the carbon fairings mounted to the Black rims loses 50-90 grams of aerodynamic drag compared to a conventional wheelset, which translates to around 25-40 seconds over 40k or five to eight watts per second. Those gains don't come at the expense of handling, though, as the blunted inner edge of the rim manages lateral air flow better than a true NACA airfoil design. The rims response to sudden gusts and side winds is more predictable, so while it's still affected, the handling stays intuitive rather than violent.
The rims' aerodynamic savings are compounded by a reduction in the rolling resistance because of the Jet 4's 25mm wide C2 rims, which increases the tire's volume and contact patch for lower rolling resistance, more grip in corners, and a more vertically-oriented side wall that is better able to deform around irregularities in the road surface. You can run a lower PSI for increased comfort without sacrificing efficiency. The tire shape also means the transition air makes from the edge of the tread to the end of the rim is smoother, resulting in still less aerodynamic drag.
The Sonic Black hubs are virtually the same as the previous Sonic models, running ABEC5 bearings on oversized axles with wide flanges for a stiff, lateral bracing angle that any rider approaching HED's suggested weight limit of 225 pounds will appreciate. The rear hub has high flanges and a grease port, so you can power wash and re-lube the wheels as needed. Both quick-release skewers have titanium shafts, and the ratchet ring in the rear hub is also titanium.
Please note that HED suggests using brand new brake pads with the Jet 4 Plus Black wheels. The same metal shavings that hide out in used pads and tend to destroy carbon wheels may also damage the Black rims' finish.