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Old 01-13-06 | 05:47 PM
  #15  
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DiegoFrogs
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From: Scranton, PA, USA

Bikes: '77 Centurion "Pro Tour"; '67 Carlton "The Flyer"; 1984 Ross MTB (stored at parents' house)

Originally Posted by harryhood
hey shants,
that's a great explanation.

however, i want to address the "if you skid in 2 opposite positions it will double the number of skidspots."

gear ratio 3.0 (e.g. 48x16)
if you skid in 2 opposite positions, it will yield double the # of skidspots. a half revolution of the cranks will turn the rear wheel 1.5 times, which results in a new skidspot.

gear ratio 2.0 (e.g. 40x20)
if you skid in 2 opposite positions, it still yields only 1 skidspot. a half revolution of the cranks will turn the wheel once, which means you'd be skidding on the same spot.

after carefully thinking about this, i think it ends up like this: if your gear ratio is an even whole number, using 2 opposite crank positions for skidding will not double the number of skid spots.

however, this makes me wonder if this has any ramifications for other less even gear ratios. but can't quite get into thinking about that now.


Actually, (and I haven't done any math to back this up...) I think that whether the chainring has an even or odd number of teeth determines this. An odd number of teeth will ultimately double one's skidspots, provided one is capable of skidding with either foot forwards.

I leave it as an exercise to the reader to demonstrate (or prove!) that the oddness of the cog is irrelevant. Mostly because I'm lazy.

Edit: Nevermind! The lucidness provided by a little more coffee has shown me what an idiot I am. Disregard.
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