I just bought a Shimano LX Crank and am looking to get a bottom bracket for it. I've been looking at external bottom brackets (and this seems like a dumb question) but I don't know how it will work if I get one because I don't have the axle thing that connects the two arms and runs through the bottom bracket. What is that thing called and where can I get it?
It sounds like you have the normal Octalink style of crank. You can't use the external bottom brackets on cranks that weren't designed for them.it's a whole different system. You'll need to just buy a Shimano bottom bracket for the cranks you have, or return them and buy a newer model that's made for external. The good news about external bottom bracket cranks is that you can use any bottom bracket for them (with the exception of the Truvativ cranks, which use their own proprietary GXP bottom bracket). This means if you buy another Shimano crank, you can still use the kick *** Race Face external bottom bracket cups if you want to. If you're doing the work yourself, you'll also need to pick up a wrench or socket that will install the external cups.they all (including Truvativ) use the same style. If you stick with the Octalink style you have now, you might also need the socket to install that style of bottom bracket. Hope this helps some. If you need more info or help choosing, post up again. :o)
External BBs are specific to the types of cranks. On Shimano chainsets look for ones that mention Hollowtech II
