ST600 project – need some replacement parts as usual

Remember my comment about not expecting any issues?  Apparently my expectations weren’t rooted in reality.

My plan to just service the existing bottom bracket ins’t going to work.  While I was cleaning the old grease off the bearings and retainers, I noticed that some of the balls had deep scratches in them and there was some rust on the retainers.  Crap.  So the drive-side cup had to come off, because I’m going to replace the BB with a new cartridge unit.  Doesn’t make sense to complete the build only to have to replace the BB in a couple of months, when it is much easier to do that now.

So I used a threaded rod with two fender washers and two nuts to clamp the adjustable wrench against the flats, and 2 minutes later the DS cup was off.  The spindle was 121mm long, and was asymmetric, with the DS being longer than the NDS.  I searched around for a while trying to confirm that the UN55 BB was or wasn’t asymmetrical, and finally was able to confirm that the 122mm spindle length has an asymmetric spindle.  Ordered the new BB, so that should solve the problem.  I think I have the correct tool for this BB, but that remains to be confirmed.

The replacement chain is here, the new BB should be here Monday, as should the freewheel tool.  Then I can remove the freewheel and send it off for a day at the freewheel spa.

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