Thread: Physics problem
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Old 07-09-15 | 01:28 PM
  #30  
nlerner
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Originally Posted by jimmuller
Consider the time duration of each of the rubbing events. The crank arm thickness is maybe equivalent to two chain links. The ring was, what, a 52T? The constant rubbing would be in effect for 26 times longer. Both would be at approximately the same radius to the spindle. So unless the derailleur-strike event applied 26 times more ******ing force, the rubbing would definitely produce more drag.
Jim, good to see you finally putting that advanced degree to work.

Originally Posted by USAZorro
You might be able to have the best of both worlds. Can you position the FD so the chain rubs and the crankarm hits it?
That's brilliant!
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