For a 1951 Black Shadow, what is the correct factory thread profile for primary drive shaft that accepts the PD 7 nut?
I know the size & pitch (3/4-20), but I don’t know the thread profile, ie BSF, BSW, CEI?
My threads are a bit buggered, and I am looking for a threading die to clean them up, but I don’t want to make a mistake using the wrong threading die and ruin my crankshaft.
I was hopeful that someone might have access to factory drawings or engineering data.
I know the size & pitch (3/4-20), but I don’t know the thread profile, ie BSF, BSW, CEI?
My threads are a bit buggered, and I am looking for a threading die to clean them up, but I don’t want to make a mistake using the wrong threading die and ruin my crankshaft.
I was hopeful that someone might have access to factory drawings or engineering data.