What does that "LL" mean, stamped (along with the length) on my Mountain Bike's Shimano BB spindle?
I don't know anything about bottom brackets, but I found this document which says (on page 16):
Shimano cartidge-bearing bottom-bracket spindles are marked with letter codes that correspond to different length spindles. These codes and the corresponding spindle lengths are:
MM 107mm and 110.5mm