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Park Tool

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BBT-147-12 Steel Bottom Bracket Tool
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Park Tool
The Park Tool BBT-147-12 Steel Bottom Bracket Tool is a precision-machined 4140 steel workshop tool for removal and installation of threaded bottom brackets with 12-notch T47 tool fittings. The BBT-147-12 fits 12-notch fittings with a major diameter of 50–53mm and a minor diameter of 48.2mm — a spec range covering Chris King ThreadFit T47, ThreadFit 30, ThreadFit T47 24x, and ThreadFit T47 30, as well as BBInfinite T47, Hambini T47, Rotor T47 External 30mm, and multiple Rotor thread-together standards including BBright, BB30, BB386EVO, and PF30. The extra-deep body handles extra-wide spindles, and low-profile walls at the engagement point reach recessed lockrings that standard-depth tools cannot access. Three drive options — 3/8" drive, 1" hex, and 36mm wrench flats — tackle even heavily seized cups, and integrated threads accept the Park Tool BBT-RS Bottom Bracket Tool Retaining System or GPS-1 Guide Pins (each sold separately) for improved alignment during service.
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Makes switching chainrings very easy… although you do need a specific tool for the job.
The new price for a replacement for my gen2 is silly. This one is better price and works, you just have to swap the bash guard and bumper at top. This is a better price and I also got a sale discount. much more reasonable. Thanks!
I'm glad I bought these guards. They do what they're made for: No more bruised or bloody ankles from smacking rocks or cranks. I do have to say, however, that the photo seems a little misleading to me. I thought these would have a smooth finish like other G-Form products, based on the photo. Instead, they are fabric, so only time will tell on durability.