Quoth Mark Bulgier:
>This is where Sheldon is a little bit wrong when he says "Note that all
>of the loading on both cotters occurs when you push on the left pedal."
>That's true for the case of pedaling, which is most of the ride, true,
>but doesn't account for the time you spend coasting over bumps or
>downhilling with the right foot forward. There the forces are fully
>reversed. And if you hit some big bumps in that position, the magnitude
>of the force can be higher than even strong pedaling.
> Thus you can get
>TWO dents in each cotter (if they are a little loose, allowing them to
>become dented), not just one dent each which would be the case if only
>the left crank forces mattered.
>
>Maybe that's why I got in the habit of coasting with the left foot
>forward?
Actually this is a good habit to develop with any 2 or 3 piece crank system. Coasting "goofy footed" (right forward...this is a term from the world of surfing) puts unnatural stresses on the crank/bb interface, and greatly increases the risk of premature failure.
Sheldon "Surfer Dude" Brown
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| People who go broke in a big way never miss any meals. |
| It is the poor jerk who is shy half a slug |
| who must tighten his belt. --Robert A. Heinlein |
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