A shy person asked:

I've a K2-1998 bike with 8 speed LX front. The current bracket has size
73-114 measured. (I suppose it should be 73-113) As you may expect it
has the square axle to mount the crack on. I want to mount a 9 speed XT
which has octalink. What new octalink bracket should I fit 113 or 118mm??

When Shimano recommends two different BB spindle lengths for the same
crankset, it mostly has to do with the diameter of your seat tube.

If you have a typical older steel frame with a 1 1/8" (28.6 mm) seat
tube, you want the shorter BB, for a 47.5 mm chainline.

If your bike has a fat seat tube, however, this means that the front
derailer mechanism is going to be farther out from the bike's
centerline, and the cage might not be able to travel far enough inward
to downshift reliably. For such bikes go with the longer option, for a
50 mm chainline.

More on this at http://sheldonbrown.com/chainline

My guess is that your bike probably would be best off with the longer size.

Sheldon "By The Numbers" Brown
+---------------------------------------------+
| Life is made up of sobs, sniffles, and |
| smiles, with sniffles predominating. |
| --O. Henry |
+---------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com