SPEEDHUB 500/14 revised permitted transmission factor now 2.1!

The permitted sprocket ratios for the SPEEDHUB 500/14 were set to ensure the hub would not be damaged due to a high input torque. These limits were set identical to the lower limits of derailleur systems of the day (2.35) but these obviously also contained a small buffer.

Current derailleur systems offer lower gear ratios now which are particularly favored by 29er cyclists for hard off-road climbs. Due to the increased interest in these bicycles the Rohloff AG has reviewed our permitted ratios and reduced the transmission factor further to just 2.1 for solo cyclists under 100kg. The 'buffer' that the SPEEDHUB previously had available is not longer present and this new factor must not be reduced further.

Gear-meters Table Online

Gear-meters Table PDF

SPEEDHUB equipped bicycles may now achieve 1.36m per crank revolution in their lowest gear without risk of losing warranty cover.

Calculating the Transmission factor:

  • 36 tooth front chainring with a 17 tooth rear sprocket = 36:17= factor 2.11 (updated Table can be found in the Owners Manual, page 20).

The Transmission factor of 2.5 still applies for Tandem use and cyclists weighing over 100kg!