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Old 06-21-21, 04:04 AM
  #98  
Kimmo
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It's a physical limitation of the derailer drivetrain that any given jump in the number of teeth between cogs gets bigger as the cogs get smaller, and once you're down to one tooth jumps the gap gets bigger as you faster - which is the exact opposite of desirable, as evidenced by gaps that go 4,3,3,2,2,1,1,1,1,1 or whatever.

The only ways to mitigate this are either shorter chain pitch, bigger rings and cogs, and/or more chainrings. The 38/50/52 combo I identified makes such a nice ratio curve I guarantee it'll be a thing if civilisation persists long enough. It changes the line from an upwards curve once you hit the one tooth jumps to a straight line. And it could be retrofitted to existing cranks as a slightly offset small ring and a double big ring, which I suspect could be made to shift quite smoothly with modern tooth profiling techniques, with the shifting taken care of by electronic syncro.
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