BB difference

[rogerzilla]

HT2 BBs are a bit more fussy about threading and facing than square taper cartridges, but a half decent Taiwanese frame should be prepped sufficiently. The fussiest BBs are probably traditional cup and cone types, and even those work acceptably well in BSOs. I would probably chase and face, but I have the tools.

 

[weareHKR]

If you have any cups from an old BB (both ends) you can make the tools to chase the threads out of your BB.
Make two narrow cuts across the threads 180deg to each other, screw them in & out & bobs your uncle!

 

[Drago]

The tiagra BB fitted to my Roubaix wore out after 4000 miles. I replaced it with an Ultegra one which is still showing no sign of wear after 17000 miles.

I had exactly the opposite experience.

 

[ianrauk]

The tiagra BB fitted to my Roubaix wore out after 4000 miles. I replaced it with an Ultegra one which is still showing no sign of wear after 17000 miles.

Yet for me its been the other way round. Ultegra failed much quicker than the Tiagra one I currently have.

 

[Gunk]

When I rebuilt my sons bike with an Ultegra groupset, I used a Tiagra chain and BB. They’re a bit more robust and the weight penalty is negligible

 

[chris-suffolk]

I had exactly the opposite experience.

I've tried Tiagra, Ultegra and XT (MTB in the hope that the seals were better). None has lasted any longer than any of the others - about 3-4000 miles. Always seems to be the left hand bearing that gets rough.