Shimano Free-wheel BB



mejess1964

New Member
Jan 6, 2013
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I have recently acquired an old Centurion Omega FF-PPS. It's the one with the free-wheeling BB. I took the cranks off and removed the crank intending to clean it up and grease it. I got it apart and then left it on my work bench for a few days. Now I can't remember how it goes back together. I have tried looking it up on the net. I either have some pieces missing or mine is a bit different. Does anybody have any experience with this old system? Does anybody know where I can find some old pictures or drawings with a schematic that shows how these pieces fit?
 
In case you are still wondering ... here is the basic information which I think you are looking for ...

First, you need to look at the various components in front of you ...

  1. two (hopefully) sets of caged bearings (truly loose bearings are certainly fine)
  2. if your bike has a Double Crankset, then the square taper spindle will be asymmetrical -- the LONGER side is the NON-driveside
  3. the two Cups will have different threads
  • the driveside cup (the chainring side) will typically have two parallel, FLAT surfaces the driveside cup will have a LEFT HAND thread (vintage French & Italian bikes which typically-but-not-always have RIGHT hand threaded driveside cups)
[*]the non-driveside cup (the bare arm) will not have a lip
  • the lock-ring will thread onto this

At this point, to paraphrase an old Russian proverb (it doesn't matter whether you bet the owl with the stick or the stick with the owl ... ) you can either install the driveside cup into the frame WITH the greased bearing assembly in place (if the bearings are loose, then you need to grease the cup & set HALF of the bearings in the grease, now) OR without ...

  • the caged bearings are inserted with the cage facing toward the MIDDLE of the spindle
  • a heavier, "marine" grease will probably need to attended to less often than a lighter grease (e.g., White Lithium ... my preference ... available EVERYWHERE) but the heavier grease will introduce more resistance

If you installed the cup, separately, then put the caged bearing on the end of the spindle whose taper is shorter & insert the assembly into the BB shell ...

Grasp the taper on the driveside ...

Place the other caged bearing on the spindle OR (if necessary) pack the non-driveside cup with grease + bearings ...

Thread the non-driveside cup into the BB shell ... adjust the lateral play out of the spindle ...

Thread the lockring onto the cup ... tighten.

BTW. I guess that different people have different ideas about how snug the bearings/etc. should be snugged, so ultimately that is up to you ... the idea is to have close-to-zero lateral play WITH a bare spindle (sans crankarms) easily turned with your bare hands ...

So, FWIW, this is how 'I' make the adjustment ...

  1. I snug the cup against the bearings (the spindle can still be turned with my bare hands, but it will feel tight)
  2. set the lockring hand-tight against the BB shell
  3. THEN, with both tools affixed to their respective counterparts, I turn the cup counter-clockwise until it meets resistance (¿possibly a 1/16th-or1/12 of a turn?) AND THEN lock the lockring against the BB shell while holding the adjustable cup stationary
  • test ...
  • some feel is necessary
  • undo if necessary & redo
  • when it feels "right" to your satisfaction then install the crankarms
 

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