See
http://www.parktool.com/repair_help/FAQohSP.shtml.
There is a special tool to open the pedals. If you can't find one, you can probably use pliers or
Vise-Grips instead. The fitting is reverse-threaded on one of the pedals; I forget which one.
Pull the spindle out of the pedal. Clean the spindle and bearings with WD-40 or kerosene or light
oil. The aim is to remove all the dirt and most of the old grease. You shouldn't have to disassemble
anything to do this. Clean out the cavity in the pedal and fill it half full of fresh grease. When
you re-install the spindle, this new grease will be forced into the bearings.
If the bearings are loose you can adjust the cones with 7mm and 10mm wrenches, but this is probably
not necessary. You can even disassemble everything and put in new ball bearings. I've done this a
few times on my road SPD pedals. But again, this is probably not necessary. If you have to do it
the balls are
3/32 inch and there are two races of 12 balls in each pedal.
Mike Yankee
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