Bottom Bracket Tap Holder BSA

Inside the 1697 BSA tap system, three pieces share the load: the cutting edge that does the thread chasing, the handle the mechanic drives, and the holder that bridges the two. The 1697.2/4 BSA tap holder is that bridge piece. It accepts the BSA tap cutters at one end and the modular handle at the other, presenting the cutter to the shell at the correct angle and torque transmission for clean thread chasing.

What this piece does

The 1697.2/4 holds a BSA tap cutter (right-hand for non-drive, left-hand for drive) and couples it to the modular handle. A complete BSA chasing operation needs two of these (one each side of the shell) plus two handles, two cutters, and the guide frame; the holder is the piece that translates handle torque into thread-cutting force without flexing or wandering off the cutter's coaxial line through the shell.

Compatibility

• Holds BSA-pitch tap cutters 1697.1 (1.37″ × 24 TPI, paired right-hand / left-hand)
• Couples to the modular frame-prep handle 1695.1/4BI
• Part of the same modular family as the Bottom Bracket Facing Tool 1699 and the Taps T47

Specs

• Pattern: BSA (paired use, one holder per side of the shell)
• Carries: 1697.1 BSA tap cutter (sold separately as a pair)
• Drive: square-drive interface to 1695.1/4BI modular handle
• Made in Slovenia by Unior

Includes: One BSA tap holder. BSA cutters and handle sold separately; a complete chasing operation requires two of each.

Made in Slovenia, since 1919

Unior has been forging hand tools in Zreče since 1919, and is the official technical partner of multiple World Tour and downhill teams. The holder is a piece that earns its place by what it doesn't do; it doesn't flex under cutting load, doesn't introduce angular play between handle and cutter, doesn't drift off coaxial during the chase. A holder that does any of those things produces threads that look right but bind the cup at install. The 1697.2/4 is built for the negative spec.

Pro tip from our mechanics

Two holders running simultaneously is the BSA chasing setup, and the geometry only works if both holders are mounted with the cutter stamps reading correctly (L on drive side, R on non-drive side). Cross-mount one and the taps fight each other through the shell. Check the stamp orientation before threading the cutters into the holders, not after the handles are on.

A holder showing visible play around the cutter retention (cutter rocking in the holder under finger pressure) is a holder that needs replacement; that play translates directly into off-axis cutter pressure and a galled shell. Inspect the holder-to-cutter fit before each BB-prep session on a busy bench.

The BSA-shell walk-through covers the dual-holder simultaneous-drive sequence and how to read the chip pattern as the cut progresses: Frame prep: threaded bottom bracket shells →