Originally Posted by
Tourist in MSN
The people doing the efficiency studies usually bought new equipment. And most Rohloff owners will tell you that their hubs got smoother over time. And I think there was some change in the seals that improved how they roll, but on that I am not sure the details or when that occurred.
Is my Rohloff less efficient than a well lubed new derailleur system? It probably is. But I noticed it was running much smoother by the time I did the first oil change. It just seems to get better year after year.
There was a followup to that study that suggested that there was less friction loss than the study you cited.
https://www.hupi.org/HParchive/PDF/hp55/hp55p11-15.pdf
This raises another point, some studies have shown a measurable efficiency loss if jockey wheels (or pulleys) are used for chain tensioning on an IGH system, where sliding dropouts or eccentric bottom brackets have less friction loss.
And a lot of people are using belts on Rohloffs, the friction losses on belt systems starts yet another debate.
I do not know what you are asking. Can you be more specific?
That study referenced in the link was conducted/sponsored by Rohloff. Chester Kyle's response to the study in the journal is worth considering unless one can pedal at 400 watts. Kyle thinks 200 Watts at 75 rpm are more realistic test method parameters than what Rohloff used although he seems to agree that the Rohloff's efficiency is relatively improved at higher wattages but contends the rankings would stay the same. So, the Rohloff
might be even less efficient at brevet speeds. 200 watts is a massive of power to average on a long brevet. Another study used 1 HP input. Also unrealistic. Kyle's assessment of the Rohloffs efficiency might actually be optimistic at brevet speeds.