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Bontrager left crank, break at pedal eye The dark-colored part of the break was the initial break, exposed to weathering. The light-colored break was the last part to break, suddenly throwing the rider onto the ground. Notice that most of the dark-colored break was on the outside of the crank, the inside being channeled. One exception is at the lower right of the photo where an inside crack had started. The innermost pedal thread is also cracked. Crank courtesy of Bill Sherwin