Road Cycling - Bottom Bracket type

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View Full Version : Bottom Bracket type


HoHoHo
07-31-04, 06:15 AM
Here's another newbie question:

How can I tell if I've got a square or Octalink bottom bracket?


Walter
07-31-04, 06:56 AM
Square taper spindle is essentially, well, "square." Spindle has 4 flats and the matching crank arms slide on the flats and are then pressed on by torquing the bolt. Crank arms have a square hole that "faces" the BB shell. Cranks have been done that way for a long time. Any older bike is square unless it's cottered but that's unlikely. Any Campy bike, new or old, is square. Some Shimano is square, some is Octa.

An OctaLink spindle ends with a "star" type pattern with 8 arms and matching crank arms are the same.

There's also Isis Drive which, I think as I haven't seen/used, is similar to OctaLink.

:beer: