Burley Hudson BB Size w/Deore XT crank - Help

[telecraig]

I need to figure out what size BB I need for my Burley hudson using a Shimano Deore XT crank (Mtn crank). 

I dropped of my burley at my LBS and they have tasked me to find out the BB size.  They are rather busy and do not want to guess at the size.  They were unable to find a reference and would like me to run it to ground.  I am rather certain it is a 68x113.  I believe what is in question is the overall length - 113/118 etc - in relation to the chain line with the Shimano Deore XT crank (FC-M751).

Thanks for the help.

[BrianW]

I have an XT crank on my Co-Motion steel frame (135mm rear spacing), and use a 113mm length square-taper BB. And, the width of the shell is easily found by measuring your BB shell (either 68 or 73, probably 68).

I'd also find a new LBS if they can't figure out something this simple themselves. Or, better yet, buy yourself the install tool (they are cheap) and do it  yourself. Very easy to do, and then you'll know how to do it! It's as easy as screwing a bolt into a hole.

[telecraig]

I think you are right - I should just buy the tool and BB myself.  It is a 68 and I think it is a 113.  I loooked into this and it appears to be easy enough.  Where I may run into problems is with the FD and RD as well chain adjustments.  Any thoughts?

Thanks again.
Cheers

[paddleboy17]

The BB is really determined by the crank you have.  You should be able to go to Shimano's web site and see what they list.  Of course when the original BB is pulled, it should be marked.  It is pretty easy to put the old one in a baggy and go from bike shop to bike shop until you find one.  I would be surprised if you had to go to a third bike shop.  You can always mail order one from one of the usual suspects.

[BrianW]

What crank and BB do you have on there now? I think the Hudson came with a Truvativ crank, from specs I see on the Net. Is it an ISIS drive BB or a square taper (ISIS I'm guessing).

Anyway, you shouldn't have any chainline issues with a 113mm BB. Depending on your old crank and chainring sizes,  you may need to adjust the FD some, either lowering it down on the seat tube, adjusting the upper/lower limit screws, or both.

[telecraig]

Thanks for the responses and advice.  I bought the frame as a NOS and did not have a BB on it.  The Shimano web site states 113 or 118.  Any thoughts?  They have the both BB in stock.

I'm giving the LBS till Tuesday to figure it out.  If it is not done by then, I will take it elsewhere or do it myself.  I think where I would struggle doing it myself is properly aligning / adjusting the FD and RD.

Cheers