While it is widely known that the V700 motorcycle introduced by Moto Guzzi in the 1960s was designed by engineer Guilio Carcano (along with Umberto Todero), the myth that it was derived from "a tractor" (the 3x3 Mulo Meccanico, or mechanical mule) has been so often repeated to have become (wrongly) accepted as fact. Many thanks to Greg Field, Moto Guzzi Big Twins, MBI publishing, 1998, for his outstanding research on this.   Beyond that, though, many would say the concept of a shaft dr