Originally Posted by
cedricbosch
Hmm, unfortunately it doesn't seem like anyone has done scientific testing on these things.
Here are a couple of articles on IGH versus derailleur efficiency from the IHPVA Jourmal. The first is by Chester Kyle and Frank Berto. The second is by Rohloff engineers. IMO both are interesting and instructive including the variations in derailleur gear train efficiency depending on gear selection.
http://www.ihpva.org/HParchive/PDF/hp52-2001.pdf
http://www.ihpva.org/HParchive/PDF/hp55/hp55p11-15.pdf
There is also a chapter in the book "Bicycling Science", third edition with additional information. The book is from MIT press and is available on Amazon for under $20 if memory serves.
__________________
Gear Hubs Owned: Rohloff disc brake, SRAM iM9 disc brake, SRAM P5 freewheel, Sachs Torpedo 3 speed freewheel, NuVinci CVT, Shimano Alfine SG S-501, Sturmey Archer S5-2 Alloy. Other: 83 Colnago Super Record, Univega Via De Oro
Visit and join the Yahoo Geared Hub Bikes group for support and links.
http://groups.yahoo.com/group/Geared_hub_bikes/