Thursday, October 28, 2010

Pedal's Anatomy (two)

Step one: unscrew the dustcap. In mid to high quality pedals the dust cap is made from steel or aluminium, it's intended to seal off the inner parts from moist and dust. The thread should provide a good enough labyrinth seal to keep the greased ball bearings clean.
Some makers claim that a specific wrench is needed but if you are a bit handy any pair of pliers will do.  Anyway, I'd just advice you to put a strap of cloth between the plier's jaws and the piece to be removed, it does not improves the grip but prevents damage to the surface of the  cap.
When the dustcap is removed  the pedal's "dark side" is unveiled.
(note: the dumbell is just a support used to take the picture)


Now we can see an hex nut blocking our way . This nut is intended to block the pedal's inner mechanism to the desired adjustment. To remove it we must use a 12mm hex wrench while holding the other end of the axle with a 15mm pedal wrench (the one used to
attach/remove the pedals).
Removing the hex nut exposes a small blocking washer (the type with a lip that run's into a slot cut through the axle's thread) . Pry out the washer with a small flat screwdriver to gain free access to the adjusting cone. Use your fingers to unscrew the cone.  This pic shows the cone, its upper part looks like a second hex nut but its underside is conic (trust me)

Now we can see the ball bearings. There are twelve of them but it looks like there's room for more (probably it is not the first time this pedal's been overhauled and perhaps some bearings rolled away forever  while in it)

Removing the ball bearings without losing one or two of them requires mastery but it allows us to examine the ball race . I use a magnetized screwdriver and then shake off the hanging bearings inside a pot with kerosene (it's a great degreaser that leaves an oily protecting film over metal pieces).
Now comes the most delicate maneuver:  carefully pulling out the axle exposing the inner bearing race (the inner cone is built in the crank's end of the axle's body). Mind that there's a full set of ball bearings (that for any unknown reason tend to roll out and get forever lost). Same cleaning process than with the outer bearings.

It's time to examine the races, they must be uniformly smooth with no pits.

As I mentioned above, when extracting the axle don't forget that the ball bearings of the inner side tend to fall down. Be careful. There were thirteen of them (it supports my theory of the "missing bearing")

 So this is it. You can see the  assembling order all the components of a Rossignol platform pedal.

Assembling process in a next post.

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