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Park Tool

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BBT-135-12 Steel Bottom Bracket Tool
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Park Tool
The Park Tool BBT-135-12 Steel Bottom Bracket Tool is a heavy-duty workshop tool machined from precision 4140 steel for removal and installation of threaded bottom brackets with 12-notch tool fittings. The BBT-135-12 fits 12-notch fittings with a major diameter of 48–50mm and a minor diameter of 46.3mm, including Praxis Works M30 bottom brackets — a standard found across a wide range of contemporary road and gravel drivetrains. The extra-deep body handles extra-wide spindles, and low-profile walls at the engagement point seat into recessed lockrings that standard-depth tools miss. Three drive options — 3/8" drive, 1" hex, and 36mm wrench flats — handle even heavily seized 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 stability 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.