How do i find the belt size?

i have a 1964 simplicty brodmoor 707 with a white half steering wheel its a beast it has ag tires but its so slow! i told my dad he can pully swap it but the last tractor i pully swaped the clutch doesent work now he asked me to find out how to find the belt size corectly after pully swaping the back smaller so the clutch works any answers on how to?

sometimes you need to redesign the clutch.... but to find the proper belt size take a piece of rope and some tape.... make sure your clutch is pressed in and locked... wrap the rope through the pulleys the way it is ment to go. and pull it tight now mark where the end of the rope meets and add an inch to that. that should work.

If i decrees 4 inches from 9in to 5in how do i figure out the belt size just

doing what i mentioned. honestly. thats the only way i know because different size pulley changes how the belt sits so you just have to measure

well is i went from 9 to 5 a 4 inch decrees do you think 2 inches shorter of a belt would work?

no clue. lol trial and error or just measure. i couldnt tell you

well thanks anyway man!

measuring is the easiest way. sorry if i didnt help much. there is not set belt size for each pulley size set up