Search results
Results from the WOW.Com Content Network
Schlumpf Speed Drive. A Schlumpf Drive is a two-speed planetary gear assembly for use on bicycles and unicycles. It is distinct from other bicycle planetary gear assemblies in that it is located behind the chainring rather than in the rear hub. A push-button on each side of the axle allows the rider to switch between high and low ratios.
Efficiency testing of bicycle gearing systems is complicated by a number of factors – in particular, all systems tend to be better at higher power rates. 200 W will drive a typical bicycle at 20 miles per hour (32 km/h), while athletes can achieve 400 W, at which point efficiencies "approaching 98%" are claimed.
Nicolai gearbox mountain bike Pinion P1.18 gearbox installed in a bicycle frame Instinctiv Modern full suspension carbon gearbox mountain bike. A gearbox bicycle is a bicycle that uses a gearbox [1] [2] to convert torque and rotational speed from the power source, usually the rider's legs, to what is desired at the drive wheel.
Before epicyclic gears were used in bicycle hubs, they were used on tricycles. Patents for epicyclic hubs date from the mid-1880s. [5] [6] The first patent for a compact epicyclic hub gear was granted in 1895 to the American machinist Seward Thomas Johnson of Noblesville, Indiana, U.S.A. [7] This was a 2-speed but was not commercially successful.
Kalkhoff logo Kalkhoff bicycle. Kalkhoff is a German bicycle manufacturer based in Cloppenburg; it was founded in 1919 by Heinrich Kalkhoff (* 30.November 1903; † 25. September 1972) as a family bu
The basic concept of strain wave gearing (SWG) was introduced by C.W. Musser in a 1957 patent [5] [6] while he was an advisor at United Shoe Machinery Corp (USM). It was first used successfully in 1960 by USM Co. and later by Hasegawa Gear Works under license of USM.
The NuVinci CVT system has a small number of parts. [5] [6] Most CVTs have lower mechanical efficiency than competitive conventional transmissions.Since any CVT may allow a power plant, human or motorized, to operate at (or closer to) its speed of optimal efficiency, output torque or output power, the NuVinci CVT may improve a system's overall efficiency or performance compared to a ...
A very small number of bicycles use a shaft drive to transmit power, or special belts. Hydraulic bicycle transmissions have been built, but they are currently inefficient and complex. Since cyclists' legs are most efficient over a narrow range of pedaling speeds, or cadence , a variable gear ratio helps a cyclist to maintain an optimum ...