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I was hoping that someone could provide me with the precise Shimano road-bike 8, 9, and 10 speed sizes for the following:

  1. Cassette Spacer Width
  2. Cog/Tooth Width
  3. Maximum Chain Width
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up vote 11 down vote accepted

I think these may be what you're looking for. FYI, a lot of this information is available with a little searching. Depending on what exactly you are looking for, you might want to look up a document for a specific cassette as the numbers might be slightly different.

Spacer widths (From Shimano tech docs)

  • 8 Spd: 3.00mm
  • 9 Spd: 2.56mm
  • 10 Spd: 2.35mm (1.0mm for lower spacer)

Cog/Tooth Width (From Sheldon Brown)

  • 8 Spd: 1.8mm
  • 9 Spd: 1.78mm
  • 10 Spd: 1.6mm

Chain widths (From wikipedia)*

  • 8 speed - 7.1mm (all brands)
  • 9 speed - 6.6 to 6.8mm (all brands)
  • 10 speed - 6.2mm (Shimano, Campagnolo)
  • 10 speed(Narrow, Direction) - 5.88mm (Shimano CN-5700,CN-6700,CN-7900)

*These chain widths are the standard widths, which I assume are recommended. I wouldn't go wider, but a narrower chain will probably work as some chains are cross-compatible.

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+1 for being generous enough to provide an answer despite the fact that op could have easily have found the answer through Google. – PeteH Aug 12 '13 at 21:54
+1 for the same reason. – Carey Gregory Aug 14 '13 at 5:27

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