Abstract: An infinitely variable speed transmission is disclosed in which, in a preferred embodiment, a drive shaft is connected to an adjustable drive spoke disposed within a rotatable toothed wheel. The drive force received by the wheel from the input drive shaft is imparted to either a sun gear or a ring gear or both. A second ring gear may be axially secured to the first ring gear. A second sun gear may be axially secured to the first ring gear. A planetary gear engages second sun and ring gears and transmits force received by it to an output shaft. When the drive spoke adjustment causes the second ring gear, through the first ring gear, to become the driving gear the slowest output speed results. Intermediate arc settings of the spoke at any point along about a 180.degree. range results in both ring and sun gear driving the planetary gear simultaneously, but at an intermediate speed between the fastest and slowest setting.