UT-A, program NZFNR is a global search and replace (or adjust or delete) that can make changes to the data based on the value of other fields in the file.  ALWAYS make a backup copy of the file you are changing.
 
In this case, file BKBMMSTR, Action Replace, field BKBM.QTY.REQD value 1.25 and enter the filter for BKBM.COMPONENT = the part.  Press enter once after entering the part to get to the list of filters then F10 to process.

Never mind, tried it again with a space " " after the item code and it seems to have worked.
 
Why there is a space I have no idea.
 
But Thanks, much easier than changing BOMs one at a time