Taps are typically tapered un less designated a 'Bottoming Tap'. a pedal tap Thru Bike Tool supplitrs , won't be,

If really needing them, You need to go to a Machine Shop Tool supplier for a 9/16 - 20tpi bottoming tap, RH & LH..



BTW, screwing a pedal in from the back side of the crank arm can chase the threads in order to start the pedal threading in , properly..




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