Disc-like benefits without the drawbacks of discs is what the HED Jet RC9 Black offers. The 90mm depth is about as deep as you can go without resorting to a disc. The spokes make the ride quality better than a disc. And the hole in the middle means that the wheel handles better in crosswinds than a disc.
The 90mm depth is a bit deep for mass-start road racing, but in the bike legs of dus and tris, and in time trials, these wheels kill it. Its certainly more of a flatter-event depth, but if the hills are short or shallow, and you can carry speed onto them, these do fine.
The weight of the wheels, 1795g for the set, is decently light for a clincher of this depth. But weight is only a small part of the story. HED is one of the first companies to experiment with rim width. They went to 23mm, the C2 and found that tires rolled better. With that in mind, they tried greater widths, settling on the Plus, 25mm in width. Wider rims mean greater tire width and air volume for a given tire. A nominally 22mm wide tire is often 22mm on a 19mm wide rim, and goes a bit over 24mm on the Plus. With the greater air volume comes both lower rolling resistance and greater comfort. HED recommends 22-25mm for the best aerodynamics, and going over 25mm if you want greater comfort and lower rolling resistance at a slight cost of aerodynamics.
As mentioned above, these are clincher rims. HED has chosen to stick with aluminum for the braking surface. The aluminum rim improves both strength and braking. Braking is improved in two ways. One is that aluminum is generally a better material for braking. Second is HED improved on the braking with their Turbine Braking Technology (TBT). This is a permanent surface treatment that reduces dry-weather braking distances by 25% and wet-weather braking distances by 70%. As this is a directional technology, make sure youve lined up the wheel in the proper direction. HED also recommends starting the wheels off with fresh brake pads, so as not to chance embedded shards scratching the finish. The TBT starts black, and should remain that color for the life of the wheel. To keep it pristine, they recommend black-colored alloy-specific pads as well.
HED laces the wheels with bladed spokes to Sonic hubs, which are HEDs house design. The hubs are flangeless in front, calling for eighteen straight-pull spokes, and flanged in the rear, calling for 24 J-bend spokes. For greater aerodynamics, the nipples are internal, lacing to the rim. This also means the shroud itself allows in water, which drains out via a drain hole as you ride, and should not be hung on hooks.
The Plus design rim is tubeless compatible. The wheels come with their own extra-wide rim tape, which is essential for tubeless, and is a really good idea for tubed. Its also thinner and lighter than conventional rim strips. So the wheels come set up for tubed clinchers, but can be converted to tubeless with the addition of the proper valve, tires, and goo.
The wheel also comes with a valve extender and titanium quick-release skewer.
For some folks, looking to balance weight and aerodynamics, mixing a Jet RC6 Black front with a Jet RC9 Black rear, or a Jet RC9 Black front and disc rear. If you're a smaller rider or on hillier courses, the former could be better. If youre a bigger rider or on flatter courses, the latter could be better.
HED recommends 100psi max tire pressure regardless of tire size. In their testing, with the increased air volume that 25mm rims produce, a 23mm wide tire at 100psi is the equivalent of 120psi with a traditional 19mm wide rim.
The HED Jet RC9 Black helps you smoke the competition.
