Originally Posted by
timo888
Do small gains or losses in efficiency really matter to commuters, multi-modal commuters, and leisure riders?
Amazingly enough, drivetrain efficiency doesn't seem to matter to sport riders and even most racers.
That Berto/Kyle report you quoted rediscovered some 110+ year old cycling wisdom concerning the inefficiency of relatively
small cogs. Example: a 52/15 ratio (~94 gear inches) is measureably more efficient than a 38/11 (also ~94 gear inches). Despite a real efficiency difference, nearly all modern sport riders happily equip their bikes with the smallest available gear train components to save a few meaningless ounces!
The Berto/Kyle study wasn't perfect, but has been called by many the best science to date on bicycle drivetrain efficiency. I'd love to see them test again and include the Alfine, I9 and SA8 hubs.
tcs