> > I want to re-tap French threaded Mod 93 cranks to English....... It was suggested to run the tap from the backside of the crankarm. Why would this be?
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> I think your results will be best if you pre-drill or ream the hole first to a proper base ID for the 9/16" x 20tpi English tap
NO no no !! Pedal taps have the ream built into them. Do not enlarge the hole with a ream or a drill...that will only lead to failure.
Brad Luecke
Columbia MO