September 18, 2019 / Bottom Brackets

Bottom Bracket Tool Selection: Press Fit

This article will review the selection of Park Tool options for various press fit bottom bracket systems. For service procedures see Press Fit Bottom Bracket Removal and Installation. For a review of the various bottom bracket standards, see Bottom Bracket Standards and Terminology.

Preliminary Info

What Tools do I need?

Digital caliper, such as Park Tool DC-1

The “press fit” bottom bracket lacks threading both in the frame and on the bearing adapters or cups. The bearing or bearing cup will be slightly larger than the bore of the frame and is pressed inside the shell. This creates an interference fit, also known as a press fit (PF). The bottom bracket is then held in place from the pressure created by the interference. A press fit bottom bracket will have no tool fittings.

PF46 bottom bracket with no tool fitting

If the cup or bearing adapters has tool fittings, it is either a threaded bottom bracket or thread-together bottom bracket. In either case, see Bottom Bracket Tool Selection: Threaded and Thread-Thru.

Tool fittings on a threaded bottom bracket

Press fit bottom brackets vary both in the shell diameter fit and the diameter of the crank spindle they will accept. Tool choice is determined by the inside diameter of the bearing, which nominally matches the outside diameter of the compatible spindle. Measure either the inside diameter of the bearing or the outside diameter of the spindle.

Measure nominal inside diameter of bearing

Measure nominal outside diameter of spindle

It is also possible the bottom bracket cups use an adapter to reduce the inside diameter for a different diameter spindle. These adapters must be removed first, using the correct tool for the inside diameter of the adapter.

Adapters reducing a 30mm inside diameter bearing down for a 24 mm spindle

24 mm & 22/24 mm Stepped Spindles

Pressf fit bottom bracket using 24 mm inside diameter bearings

Examples include Shimano® two-piece cranks, SRAM® GXP®, and many more brands and models which feature 24 mm spindles. This includes the stepped spindles such as the SRAM® GXP® in 22/24.

Use the Park Tool BBT-90.3 for removal.

25–28.99 mm Spindle Systems

Press fit bottom bracket adaptor installed in bottom bracket shell of carbon fiber bicycle frame

Examples include Campagnolo® Power Torque™, Ultra-Torque®, SRAM® DUB®, and bottom brackets with inside diameter from 25 to 30 mm.

Use the Park Tool RT-1 for removal.

30 mm Spindle Systems

Examples include SRAM® PF46 (PF30), PF42 (BB30), Race Face® Cinch® bottom brackets, and other systems using 30 mm spindles.

Use the Park Tool BBT-30.4 for removal
Note: Some special cases require Park Tool RT-1

Miscellaneous Standards

There are other standards using a press fit system. The “Ashtabula” one-piece crank and BMX standards in Mid and Spanish press into the compatible frame shells. Use a punch and a hammer to remove these bearings.