Bottom Brackets to fit DMR Sect Cranks to your bike. DMR Sect Cranks have a 24mm diameter spindle, which is also compatible with any Shimano Bottom Brackets. BSA 68/73mm - Standard BSA english threaded Bottom Bracket. Designed to fit DMR Sect or Shimano Hollowtech II Cranks with a 24mm spindle. Fitted with fully sealed Enduro 2437 bearing