Help me determine this pulley bore size

[BigMike50]

need to order a custom pulley. Everything i find in the size i need list the bore size at 3/4 inch. My pulley doesn't seem to have a 3/4 bore size. Mine measures at 12/16. IS there something with pulleys where you just round up to 3/4 inch. I don't get it. I took a pic with tape measure. see below.

 

[tommu56]

12/16 common denominator 4

(12/4) / (16/4) =3/4


drop a 3/4 bolt in it for size.

 

[BigMike50]

12/16 common denominator 4

(12/4) / (16/4) =3/4


drop a 3/4 bolt in it for size.

cool thanks for the info. ill do that tomorrow neighbor. im right outside Phoenixville on Charlestown road

 

[Bladehauler]

looks like a 5/8 bore to me .

 

[BigMike50]

looks like a 5/8 bore to me .

thanks for the confirmation. i just went out and checked with the biggest bolt i had which fit in the bore. i then took a couple box wrenches to wrap around the bolt. turned up that a 5/8 box wrench just fit. Don't know why i didn't think of this. thanks guys