So yesterday I washed my bike which is a Stock Components Surly Straggler 2015. I noted some squeaking around the BB even after lubing the chain so I decided to clean the bottom bracket. I didn't have the tools so I went out to buy them, and funnily, when I came back 2 hours later the squeak was gone. So it must have been related to water somehow. Anyhow, I now had the tools so I wanted to use them.. I removed the left crank and then the spindle. I noted then that the BB only has the two cups, but there's no sleeve, this center plastic tube through which the spindle runs:
I wonder why my bike is missing that piece? Is it not absolutely required?
EDIT: I found the Surly bottom bracket installation instructions here and from this PDF it seems like for my 68mm bracket, no sleeve is provided:
So I guess that the part isn't 'missing', and the mention of 'Road' use in the table could suggest that they assume you don't hit any dirt. The frame does have a small drain hole in the bracket. Well, but I DO hit the dirt. Can anyone suggest a BB upgrade? It somehow seems logical that a sleeve will protect better.