Product Description You, or more specifically, your choice of frame, motivated us to address challenges related to bottom bracket installation and durability – thank you. We embraced the task to improve upon so-called bottom bracket standards to give you the UBB4630. Crafted from 7000 series aluminum alloy, the UBB4630 uses a threaded sleeve to lock both cups in place – without having all the locking effort rely on the press fit shell, thus providing a uniform spin and avoiding undesired noises. The flush fitting in the press fit region prevents bearing overload and also improves bearing alignment for a longer bearing life. The external bearing location affords a smoother spin and increased BB shell stiffness for PF30 and BBright standards. The internal sleeve also prevents cable guides from rubbing against rotating parts. *If replacing the OEM bottom bracket on a Cervelo BBright frame, check for the OEM spider using an integrated 11mm spacer. If your crank is using this wider spider, it will not be compatible with the UBB bottom bracket.
