Originally Posted by
dedhed
Don't get me wrong, I'm all for repairing things that are hard to find, original, or cost/time effective, but I'd say a UN-55 is hardly a vintage expensive unobtanium part.
I just welded up and rebuilt a worn idler pulley bracket on my lawn tractor because it was already apart and I would have had to order the $10 part and wait for it. 15 minutes with the welder and grinder and I was good to go and back together.
I thought the whole point of cartridge BB was to pull them out and replace them as needed.
The story I got from a few different industry people, back then, is that the Shimano style cartridge BBs were all about speed of factory assembly and having the manufacturer control the bearing preload (as opposed to the shop wrench or rider being able to adjust it, wrongly sometimes). The ease of replacement was the icing on the cake for the LBS service dept. but this benefits the manufacturer or bike factory very little. Andy