Bicycle wheel how well the wheel transmits propulsive and braking forces, if applied at the hub, as in the case of hub or disc brakes. Several factors affect these stiffnesses to varying degrees. These include wheel radius, rim bending and torsional stiffness, number of spokes, spoke gauge, lacing pattern, hub stiffness, hub flange spacing, hub radius. In general lateral and radial stiffness decreases with the number of spoke crossings and torsional stiffness increases with the number of spoke crossings. One factor that has little influence on these stiffnesses is spoke tension. Too much spoke tension, however, can lead to catastrophic failure in
Are Years What? (for Marianne Moore) mobile with wire, shaped like a "V". "Are Years What? (for Marianne Moore)" is signature of di Suvero's monumental early 1960s "open-work constructions." These works utilize cast-off construction materials like chains, metal bars, and ladders. This sculpture is the first that di Suvero built, from beginning to end, with I-beams and using a crane, solely by himself. "Are Years What?" was originally in the collection of the artist, then the collection of Enrico Martignoni of Winnemucca, Nevada. Hirshhorn director James Demetrion first saw the sculpture when it was on display in Brooklyn's Prospect Park. The sculpture was acquired by the