Park Tool BBT-47-16 Bottom Bracket Tool

Thread-together and T47 bottom brackets arrived with a wider tool fitting than the external cups that came before them, and 16 notches at 52-54mm is where a lot of those designs landed. The BBT-47-16 from Park Tool is cut for that fitting and nothing else: a major diameter of 52-54mm measured across the outside of the notches, 48.8mm across the inside.

The compatibility list covers most of the aftermarket: SRAM T47 DUB, Enduro T47 Internal along with the BB30/30a and BBright TorqTite thread-together units in 30mm and DUB spindle versions, Kogel T47 Inboard, CeramicSpeed T47/86 and T47A, White Industries T47 and PF30 Thread-Together, C-Bear T45 and T47-BB86, Cane Creek T47 Internal, and Campagnolo's Ekar Pro-Tech T47 x 86. If you have built up a frame around a T47 shell and swapped bearing brands once or twice already, one tool handles all of it rather than a drawer of brand-specific sockets.

Count the notches and measure before you order, because 16 notches alone is not enough information. Cups with 16 notches at a 49mm outside diameter need the BBT-27.3 instead, and several T47 bottom brackets use a 12-notch fitting that calls for the BBT-47-12. Standard external bearing cups from Shimano and SRAM sit well below this tool's diameter range, so this is not the tool for a Hollowtech II crank. Match the notch count and the diameter to what is actually on the bike and the interface engages fully, which is what keeps an aluminum tool from rounding a cup under load.... Read More