[Dekes]

I was taking apart my bike and saw this weird bolt at the non-drive side of my BB. It would be nice to unscrew it so i could maybe clean the inside of the bb. I have no clue though whether it's right-hand or left-hand thread or even whether there is thread or not. Has anyone seen this before or does anyone know if this bolt can be unscrewed or what it's function is? Thanks.

 

[Dekes]

Ah and there's a sticker on the BB that says "shimano sealed cartridge bearings"

 

[Sideknob]

I think you'll find that collar is a tight friction fit on the spindle, and serves to hold the whole lot together. Just for kicks, I have bashed on the end of the spindle of an old bottom bracket to see what's inside. It takes a lot of force to move one of those things and you'll trash the rest of the assembly in the process.