05-17-10, 08:19 AM
I need a shorter bottom bracket for my 1984 Schwinn World. It currently has the original with male threaded ends. I am trying to back into the measurement of the chainline relative to the end of the square taper part of the spindle, because I don't have my tools to remove the cranks right now. I know that the chainline is 18mm inside of the end of the male threaded tip, but I need to know how long the male threaded tip is to subtract it from 18mm. Does anyone know how long the male threaded tips are (if they are standard)? Is there another way to find out what size bottom bracket is needed for a given chainline without removing the cranks?