When it comes to climbing, shallow rim depths are ideal. And when it comes to training, aluminum reigns supreme. However, too often, wheel makers force you to jump from the heights of carbon-heaven to the pit of despair that can be the aluminum clincher. Not anymore. With the new Zipp 101 Clincher, Zipp applied the same toroidal design that"s propelled its Firecrest technology to the forefront of the peloton. Lightweight, aerodynamic, and just plain ol" fast, the Zipp 101 Clincher is the obvious choice for your day-to-day wheel. Zipp"s foray into aluminum clinchers resulted in a patented aerodynamic design that, compared to its closest aluminum competition, shaves up to 42 seconds over 40 kilometers. With first impressions like this, we"re ready to let the Zipp 101 marry our daughter and take the keys to the sports car. The Zipp 101 shares many of the characteristics seen in Zipp"s carbon series of race wheels. The 101 features a tunnel-tested, fully toroidal rim shape as well as many of the Firecrest"s wider-is-better design features. Don"t worry if you don"t know what a "toroidal rim shape" is -- it"s been a while since our last geometry class, too. Here"s an easy explanation. Whereas a traditional aluminum rim follows a "V" shape from the spokes to the rim bed, a toroidal shape follows more of a "U" shape. It sounds elementary, and perhaps a bit fussy, but the benefits are staggering. With the 101"s design, Zipp is able to tune the brake track width independently of the rim"s maximum width -- that"s why the 101 is touch narrower at the rim (22.98 to 23.79mm). Having the freedom to choose where the widest point on the rim needs to reside on the section allows the modifications necessary for Zipp to increase braking power, improve aerodynamics, and decrease crosswind sensitivity. Even today, this shape is the basis for the venerable Firecrest crest technology applied to Zipp"s carbon lineup.