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Old 08-22-07, 07:58 PM
  #51  
HillRider
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Join Date: Aug 2005
Location: Pittsburgh, PA
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Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

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Originally Posted by rmfnla
A rotating shaft (pedal axle, BB spindle) exhibits orbital motion in the direction opposite to its rotation.
Could you explain this further? How does a shaft turning between two sets of bearings orbit?

Originally Posted by rmfnla
If the balls are generating enough friction to affect a properly tightened pedal or BB someone needs to learn how to adjust bearings.
The balls are rotating counter to the direction of the spindle. The bottom of each ball where it contacts the spindle moves in the direction of the spindle causing the top of the ball where it contacts the outer race (bb cup or cartridge shell) to turn in the opposite diredtion and, in effect, tend to tighten the cup if the threads are pitched correctly. Of course the friction isn't much but it isn't zero either.
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