"Sprockets"

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The Rohloff SPEEDHUB 500/14 comes fitted with a 16 tooth reversible sprocket. 15 and 17 tooth reversible sprockets are available as alternatives. Hereby, an individual chainring/sprocket combination can be applied. The 15, 16 and 17 tooth sprockets are reversible, and therefore, can be used from both drive sides. For sprocket removal, a special Rohloff sprocket tool is needed.

Sprocket with 13 teeth

For the use of the Rohloff SPEEDHUB 500/14 on small wheeled bicycles (e.g. 20", folding bikes and recumbents) the special 13 tooth sprocket is needed. It uses a different chain line (58mm instead of 54mm) and is not reversible. When using a Rohloff chain tensioner on frames with dropouts thinner than 7mm, the longer chain tensioner mounting bolt must be separately ordered. For sprocket removal, a special Rohloff sprocket removal tool is needed.

The Rohloff SPEEDHUB 500/14 has been developed for racing which means that it can handle the heavy loads encountered during competition. Maximum torque loads in extreme conditions can be as high as 250Nm on the crank (= 150kg on the pedal). This will not damage the gear box because the high chainring/sprocket ratio transforms the low number of crank revolutions into a higher number of revolutions at the cog.

The higher the chainring/sprocket ratio, the lower the input torque to the gear-unit. It is imperative therefore that the chainring/sprocket factor does not drop below 1.9 (e.g. 34/17=2.0). The smallest permissible sprocket ratios for a rider weighing less than 100kg are: 32:17, 30:16, 28:15 and 26:13.

These are the equivalent to a 22:40 combination on a conventional drivetrain. There is no limit whatsoever for higher ratios which means that you can mount bigger chainrings than shown on the table for extreme downhill racing.

If the SPEEDHUB is mounted on a tandem bicycle or if the rider weighs over 100kg, a chainring/sprocket factor of 2.5 (e.g. 42/17=2.5) must be upheld. This equates to sprocket ratios of:  42:17, 40:16, 38:15 and 34:13.