Choosing a Bottom Bracket...

wilmeaden

I'm a bit of a novice and could do with some help in choosing a bottom bracket for a new crankset on my mountain bike! I'm replacing the whole drive train... it's a 24 speed and I've put a new rear cassette and chain on already.

I've chosen a new crank set; a Shimano Alivio Chainset Square Taper M410 but just quite work out what length bottom bracket I need.

I've looked at this tech doc on the Shimano website which has been somewhat helpful and have emailed them to ask but they haven't bothered replying:

http://techdocs.shimano.com/media/techd ... 667768.PDF

So I see I need a BB-UN26. But I can't work out the -K and -E means and the spindle length...

My shell size is 68mm and the previous BB I took out was 116mm. ( I don't know if this length matters...)

Do I need a 110mm, 113 or 122mm??

PLEASE HELP!

Thanks a lot[/b]