can anyone tell me the correct specs when upgrading the BB on my '06 OCR2?

the stock truvativ touro is as floppy as noodles :mad: and i can get a good deal on shimano 105 or Ultegra...but all this bottom bracketry has my head spinning.

what numbers do i need to be looking for in a bottom bracket for this bike?

i found a site that says 68mm shell width, english threads...Giant's site says nothing however.

thanks for any help!

It can be confusing, I suggest you spend some time on Sheldon Brown's site to learn more. I think before you run out to get Shimano you need to consider how your cranks connect to the BB. If your bike is 68, English, that is standard size for most American bikes so getting a BB to fit your BIKE is not an issue. I am not a Truvativ expert but I believe they are either the square type or use the ISIS standard. If you are looking to just change out the BB (and by the way the noodle-y feel may not just be your BB, but you know what your feeling!), then you have to get the same type connection on your new BB. So it depends how many gears you are running on the back, for example the 9 spd Shimano BB will fit your bike but is probably not compatible with your cranks. So your issue is that you want to start with the cranks and then find a standard bb that matches your setup (double or triple).

http://www.sheldonbrown.com/bbsize.html

b21

thanks, it is definitely the crankarms i feel flexing, my Specialized hardrock mtb had truvativ crankset and felt the same way. i'm not superman either, so i know my strength isn't overloading them or something.

the crank and bb on the bike now use the Square standard. i figure it's just simpler to get a new crankset and bottom bracket, instead of finding a new crankset with square interface (most i've found use octalink or ISIS)

if you are getting a new crankset to match the bottom bracket then you have no issue. You have a standard size, and you need to just match your drive train, double or triple.