Re: "DO NOT DISASSEMBLE" is screaming "Disassemble me!"

On 5/23/2024 12:09 AM, James wrote:

Shimano BBR60 has a warning on the plastic bearing cover, "DO NOT DISASSEMBLE", that of course makes me want to disassemble the damn thing, especially as the bearings feel like they need a clean and re-grease.
 https://www.amazon.com/SHIMANO-BBR60-Ultegra-Bottom-Bracket/dp/B00CABINCY?th=1
 So I did.  Well, enough to properly clean and re-grease the bearings.
 The plastic bearing cover has a lip that makes it very difficult to remove without damaging it.  I found an appropriately sized socket that encourages the plastic to compress sufficiently that it just pops out. The slight taper at the mouth of the socket squeezes the plastic.
 Once that is out, with a plastic pick you can carefully extract the outer seal.  There is also an inner seal.  As my frame has an enclosed BB shell, I see no need for internal seats (and the BB has a plastic shell with o-ring seals as well).  So with 2 appropriately sized sockets, I pushed the bearing a few millimeters out, and removed the inner seal and threw it away.  I used my bench vice for a bearing press.
 Then I could properly clean the bearings.  Again with a socket I pushed the bearing back in, flushed it clean and re-greased it.  Then pop the outer seal back in and the plastic bearing cover over the top.
 Re-assembled on the bike and the cranks turn beautifully.
 

Good technique.
I found a clay/wax sculpting tool while looking for something else at an art supply years ago. The diamond end is just perfect for lifting bearing seals:
https://www.pcmag.com/articles/how-to-detect-ai-created-images
--
Andrew Muzi
am@yellowjersey.org
Open every day since 1 April, 1971