>----- Original Message -----
>From: "garth libre" <email@example.com>
>Sent: July 10, 2001 8:29 PM
>Subject: [CR]Sheldon Brown and his planetary love of Sturmey Archer
>Really, my question is why not an internal 10 speed, instead of just 3,4 or 5? With carefull engineering, and >evolution of design wouldn't it be at least possible? I mean if we currently fit 10 cogs where we once had 5,
>then by slenderizing everything it should work. Why not? Garth in Surfside Libre
Derailleur gear systems have a relatively constant efficiency relative to number-of-gears, as each is a single stage. Planetary systems have only three possible ratios, so numbers-of-gears greater than that have multiple stages of gear-train, and multiple losses.
But then, sometimes I tell small children there are little mice in there doing all the work.