12-notch bottom bracket cups are everywhere now — SRAM DUB, Race Face Cinch, Rotor BSA30, Zipp Vuma, Hawk Racing BB3086 — and they all share the same tool fitting pattern but can vary slightly in diameter. Park Tool's BBT-79.3 is CNC-machined from aluminum to fit 12-notch threaded bottom bracket cups with a major diameter of 45–47mm and a minor diameter of 44mm, which covers the range across those brands. If you've pulled the crank and you're looking at 12 notches in that size window, this is the tool you need.

The BBT-79.3 accepts a 3/8" drive, so you can run it with a ratchet for quick removal or a torque wrench for dialed installation torque — which matters, because bottom bracket cups have specific torque specs and over-tightening aluminum cups into aluminum shells is a fast way to create problems. The tool body is anodized for identification and durability, and Park Tool manufactures it in-house rather than sourcing it out. One detail worth noting: this tool is not designed for use with impact drivers or other power tools. Hand tools only.

The BBT-79.3 also includes integrated threads that accept the Park Tool BBT-RS Bottom Bracket Tool Retaining System, which is sold separately. The BBT-RS uses a spring-loaded rod that threads through the bottom bracket spindle and applies pressure to keep the tool seated against the cup. That matters on stubborn removals where the tool wants to skip off the notches — the retaining system holds everything in place so you can focus on turning instead of fighting slippage. If you're working on bikes regularly, the BBT-RS is a worthwhile add-on.... Read More