Bottom bracket

Bottom Brackets & Square-Taper Bottom Brackets for Classic Bicycles

At Sella-Berolinum, you will find bottom brackets and bottom bracket cups for classic bicycles, road bikes, and custom bicycle builds. Our range includes square-taper bottom brackets with JIS and ISO interfaces, as well as matching bottom bracket cups for various bottom bracket threads.

In addition to the widely used BSA/BSC standard, we also offer solutions for rarer vintage frame standards. These include French, Swiss, and Italian bottom bracket threads – particularly useful for repairing and restoring classic bicycles.

Our range includes, among other items:

  • JIS square-taper bottom brackets
  • ISO square-taper bottom brackets from Spécialités TA
  • BSA/BSC bottom brackets and bottom bracket cups
  • French bottom bracket cups M35 × 1
  • Swiss bottom bracket cups M35 × 1
  • Italian bottom bracket cups 36 × 24 TPI
  • Bottom brackets for various axle lengths and bottom bracket shells

When choosing a square-taper bottom bracket, four specifications are particularly important: the JIS or ISO square-taper standard, axle length, bottom bracket shell width, and bicycle frame thread.

Especially with older bicycles, the existing thread standard should be carefully checked before ordering. For example, French and Swiss threads can both be designated M35 × 1, but differ in other ways, including thread direction.

In addition to standard bottom brackets, Sella-Berolinum also offers special Sellax bottom bracket cups and components for increasingly rare bottom bracket standards.

For classic and vintage frames, we also offer special Sellax bottom bracket cups for BSA/BSC, French M35 × 1 thread, Swiss M35 × 1 thread and Italian 36 × 24 TPI thread.