The Park Tool BBT-179 Steel Bottom Bracket Tool is a precision-machined 4140 steel workshop tool for removal and installation of threaded bottom brackets with 12-notch tool fittings in the 45–47mm major diameter range. The BBT-179 fits fittings with a major diameter of 45–47mm and a minor diameter of 44mm, covering SRAM BSA DUB, Race Face Cinch, Rotor BSA30, Zipp Vuma, and Hawk Racing BB3086 among others — a compatibility set that spans current performance road, gravel, and mountain drivetrain platforms. The extra-deep body clears extra-wide spindles, and low-profile walls at the engagement point reach recessed lockrings that shallower tools miss. Three drive options — 3/8" drive, 1" hex, and 36mm wrench flats — address even the most seized bottom bracket cups, and integrated threads in the tool body accept the Park Tool BBT-RS Bottom Bracket Tool Retaining System or GPS-1 Guide Pins (each sold separately) for improved alignment and stability during service.
Machined from 4140 steel for heavy-duty workshop use
Fits 12-notch threaded bottom bracket tool fittings with a major diameter of 45–47mm and a minor diameter of 44mm
Compatible with SRAM BSA DUB, Race Face Cinch, Rotor BSA30, Zipp Vuma, and Hawk Racing BB3086
Extra-deep body accommodates extra-wide spindles
Low-profile walls at the point of engagement reach recessed lockrings
Three drive options: 3/8" drive fitting, 1" hex fitting, and 36mm wrench flats
Outer diameter at point of engagement: 50.04mm (1.97")
Internal clearance: 42mm (1.654") depth x 30.44mm (1.198") diameter
Integrated threads accept Park Tool BBT-RS or GPS-1 Guide Pins for added stability (each sold separately)
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Joshua
⭐⭐⭐⭐⭐
Everything was great. Was waiting for the SL9 to release since the first leak. Going from a SL7 was night and day.
Also Sierra Bicycle Supply, was amazing. Will be shopping here plenty more. The service they displayed was top tier, from the order placing online all the way to the delivery.
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Everything was great. Was waiting for the SL9 to release since the first leak. Going from a SL7 was night and day.
Also Sierra Bicycle Supply, was amazing. Will be shopping here plenty more. The service they displayed was top tier, from the order placing online all the way to the delivery.
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