Without a doubt, Zipp took the wide-aero rim revolution and ran (or rolled) with it. But cycling icon Steve Hed has been incorporating deep rims, toroidal shapes and bladed spokes since 1989 when HED introduced the 'Jet' wheel. In fact, in 1991 HED was granted the patent for the toroidal and hybri-toroidal rim design. HED's rim shape was ahead of its time, and other manufacturers have been playing catch-up ever since.
The HED Stinger 4 Carbon Tubular Wheel benefits directly from Steve Hed's original rim design. The C2 platform rims are 46mm deep and 28mm wide on the outside, as compared to most rims that are only 19mm wide and 19-23mm deep. The reason for the greater width is because 23mm tires really are, for the most part, the minimum tire width you should be using on the road. A 23mm tire on a wider rim changes the tire's footprint, so it grips better in a straight line and it grips better in turns because the tire deforms more evenly. A 23mm tire on a 28mm rim also has lower rolling resistance.
If you're planning on wrapping the Stinger 4s in even wider tires (e.g. 32mm cyclocross or Roubaix tubulars) you'll no doubt be pleased with the outcome. This is because the wider rim better supports the larger tire volume, preventing the tire from mushing around or feeling sloppy. In addition, the wide rim shape also means more contact between the rim and tire, which in turn means that it's much harder for the tires to roll off, thanks to the fact that the rims cradle the tire better and there is more surface area to which to glue it.
The Stinger 4s come standard with HED's Carbon FR Sonic hubs. The hubs have a carbon fiber center section and use a minimalist shape in order to maximize aerodynamic characteristics. Both the front and rear hubs run ABEC5 bearings on oversize aluminum axles: 12mm in front, 15mm in rear. The oversized axles are stiff, and with less deflection the bearings run smoother and with less drag. The front hub has aluminum end caps with a carbon-fiber center, and the rear hub is all aluminum with a grease port covered by a carbon-fiber cap. The pawl mechanism for the cassette body ratchets on a titanium ratchet ring.
Like to the rest of the Stinger line, the Stinger 4's front wheel is laced radially using 18 Sapim CX-Ray bladed spokes, while the rear wheel has 24 spokes laced in a two-cross pattern on both sides. The spokes are threaded to aluminum nipples. The two-cross lacing pattern on the rear was used to stiffen up the rear wheel so that no power would be lost to wheel flex, as a result more power is channeled to driving the bike forward.
The rear wheel is available to fit Campagnolo or Shimano/SRAM cassettes and the freehub bodies are easy to swap out with two 5mm hex keys. They come with valve extenders and HED titanium skewers. Any carbon-specific brake pad should work well with HED's braking track. The recommended rider weight limit for the HED Stinger 7 Carbon Tubular Wheelset is 210lbs.