I need a new bottom bracket and just need something clarifying Octalink BB's have two numbers e.g 73 118 am I correct in thinking the first number is the BB shell size and the second is the axle length?

If so would it make a difference to anything but the chain line if I got a longer Axle'd version, I think its 121, or am I much better changing like for like.

Thanks Sam

am I correct in thinking the first number is the BB shell size and the second is the axle length?

Yes, and 118 to 121 is about half a chains width so should be tolerable but obviously best like-for-like….

Grand

nearly like for like it is then managed to fine an XT over Deore so am a rather happy man
😀