Aluminum Bottom Bracket Socket BSA30 (Threaded BB30)

BSA30 is the threaded variant of the 30 mm-spindle BB family. Same 1.37" × 24 TPI shell threading as standard BSA (so it threads into a regular BSA frame), but the cups are bored for a 30 mm spindle instead of 24 mm. Race Face Cinch, Praxis M30, Rotor 30 mm cranksets, and other 30 mm-spindle cranks that need a threaded-shell installation use BSA30 cups in BSA-threaded frames. There is no ”BSA30 press-fit“ variant; the press-fit equivalents for a 30 mm spindle are PF30 (42 mm shell ID, 68 or 73 mm shell width) or PF30A (Cannondale's offset variant).

The 1671 Aluminum BB Socket cut for BSA30 fits the cup's outer notch profile cleanly without the rocking play that a generic 16-notch socket allows on a slightly different geometry. The aluminum body matches the cup's hardness; the engagement is tight enough that the splines don't lift under the 35–50 Nm install torque a 30 mm-spindle threaded cup wants.

Why a separate socket exists for BSA30

A 30 mm-spindle threaded cup is dimensionally different from a 24 mm-spindle HT2 cup, even though both thread into BSA-pattern frames. The notch outer profile, the cup OD, and the depth at which the notches sit relative to the frame face are all slightly different. A standard 16-notch HT2 wrench will engage on a BSA30 cup; but with reduced contact area, which is what rounds the notches under torque. The dedicated BSA30 socket eliminates that risk by sizing to the cup's actual geometry.

Compatibility

• BSA30 cups (Race Face Cinch, Praxis M30, Rotor 30 mm in BSA-threaded frames)
• Cups bored for 30 mm spindle with 16-notch outer engagement at the BSA30 OD
• Not for PF30 / PF30A press-fit shells; those need a press-fit BB removal tool, not a socket
• Not for standard BSA (24 mm spindle); use the 16-notch generic or BBR60 socket

Specs

• Drive: 1/2" square drive (use with a torque wrench, ratchet, or fixed handle such as the Pro Socket Handle)
• Material: CNC-machined aluminum, red-anodized
• Notch fit: BSA30 outer profile
• Includes: the socket itself; pair with the Bottom Bracket Socket Retaining Tool for low-profile cup engagement

Built in Zreče

Unior has been forging hand tools in Zreče since 1919, and is the official technical partner of multiple World Tour and downhill teams. The BSA30 socket is the cleanest example of why the 1671 family is cut to the specific cup pattern, not to a generic envelope: 30 mm-spindle BB cups landed in shops without a dedicated socket for most of the last decade, and shops worked around it with marred cups and rough notches. The BSA30-specific tool retires that workaround.

Pro tip from our mechanics

The most common BSA30 confusion in the shop is the threaded-vs-press-fit question. The BB30 standard (no “BSA” prefix) is press-fit at 42 mm shell ID, no threading involved; BSA30 keeps the BSA threading and just bores the cups for a 30 mm spindle. If the frame's BB shell has threading visible at the entry, it's BSA30; if the shell is unthreaded, it's BB30 / PF30 and this socket won't apply; the BB30 Bearing Puller handles the press-fit case.

For the install / remove procedure and torque values: Replace or clean your bottom bracket →.