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Old 09-17-10 | 07:52 PM
  #26  
MAMARONECKMARC
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Joined: Apr 2008
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Koga Miyata has begun offering the Alfine 11 with Signature Series bikes
http://www.koga-signature.com/en/Kog...e-Gearing.aspx.

What concerns me about the Alfine 11 is the low sprocket ratio. Rohloff only allows a sprocket ratio of no lower that 2.35.
http://www.rohloff.de/en/products/sp...ios/index.html

Koga Miyata installs a 42T/16T setup for a healthy ratio of 2.63. Koga Miytat sells bikes with the Alfine 8 at a ratio of 2.21 (42T/19T), which is slightly below what Rohloff would warranty. The Alfine 11 is a whole different story. In order to get the high gear, low gear and close gear range increments of 13%ish (except for the granny which is 29%), the Alfine 11 is set up with a 38T/21T for a low sprocket ratio of 1.80. This means that the torque forces on the Alfine 11 Hub exceed the Rohloff allowable specs by over 30% (2.35/1.80). As the Alfine 11 is brand new and of new design, I have a tough time believing it is going to withstand torque forces that a Rohloff can't.

Last edited by MAMARONECKMARC; 09-17-10 at 08:06 PM.
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