Here's a simple rule to remember which direction to turn the pedals
when removing them from the cranks:  With the wrench at the 12 o'clock
position, turn the wrench towards the rear tire.  This works for both
the left and right pedal.

The left pedal has left-hand threads (tighten counter-clockwise), so it is
the opposite of the normal right-hand treads found most everywhere else on
the bike. 

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