Originally Posted by
Crankycrank
One thing not mentioned is that the Shimano external BB's can be re-lubed. After removing the plastic sleeve just use a blade to pry off the seal and the bearings can be flushed and greased. Choose your maintenance intervals but I think even in the worst conditions every 5k miles would be safe and you may be OK with every 10k miles or more.
Thanks for mentioning that, I have seen a YouTube video of that, but do not recall which specific brand type of bb it was, but given my experience with keeping ball and cons hubs regularly regressed, this is something I would do.
Bringing up ball bearing hubs touches on quality connected with longer life. I've certainly noticed over 30 years how better quality hubs last longer, adjust better and have better seals to keep grease cleaner longer. I assume ext bb's are no different, just like square taper bb.