Rohloff Speedhub
From Wikipedia, the free encyclopedia
The Rohloff Speedhub is a 14 speed epicyclic internal hub gear for bicycles. It offers 14 equally-spaced sequential gears operated by one twistgrip with no overlapping ratios. The gear range is wider than that of competing 27-speed derailleur systems. The Speedhub 36 500/14 has a gear range of 526%, which means that the highest gear is 5.26 times higher than the lowest gear. Across the entire range of the 14 gears shifts increase or decrease in even increments of 13.6%.
The mass of the Rohloff is comparable to that of a triple-chainset derailleur drivetrain with a similar spread of ratios, but being completely sealed it requires substantially less maintenance, especially when combined with a full chaincase. It can be used with a wider chain than most current derailleur gears, which reduces wear on the driving gears. Gear changing is smoother and can be achieved when the bicycle is stationary. Offset against these benefits, it is slightly less efficient than a clean and lubricated derailleur system and is expensive (currently around two to three times the price of a capable triple chainset, rear derailleur, cassette and hub). It is also noisy in the lower gears, although users report that the noise is much reduced as the hub wears in.
The Rohloff is much prized by all-year commuter cyclists.
