Any one know what the thread size is on the choke stud?

Spent a couple hours making a choke nob out of a peice of scrap titainium at work today came out nice (i'm a genius with a bridgeport). But time came to tap it, dont know the size.


The percentage you're paying is too high-priced While you're living beyond all your means And the man in the suit has just bought a new car From the profit he's made on your dreams